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DOI: 10.1055/s-0040-1706008
Methanesulfonic Acid Catalyzed Friedel–Crafts Reaction of Electron-Rich Arenes with N-Arylmaleimides: A Highly Efficient Metal-Free Route To Access 3-Arylsuccinimides
We gratefully acknowledge the SERB (Research grant No. EMR/2017/000174) for financial support.
Abstract
Friedel–Crafts reaction is widely used for the C–C bond forming reaction to enable the direct connection of electron-rich arenes to electron-deficient olefins with high regioselectivity. Herein, a highly efficient, metal-free, and environmentally benign F–C strategy of electron-rich arenes with N-arylmaleimides has been developed for the construction of 3-arylsuccinimides in the presence of a green reagent methanesulfonic acid under mild reaction conditions. This highly facile and high-yielding protocol has compatibility with different electron-rich arenes.
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Cyclic imides mainly maleimide and succinimide having 3-aryl substitution belong to an important class of heterocyclic compounds. Due to their frequent occurrence in natural products and pharmaceuticals with diverse biological activity, the synthesis of these scaffolds is a dynamic field of investigation. Representative examples of biologically active arylsuccinimides[1] are given in Figure [1]. One of the great advantages of maleimide and succinimide motifs is that they can serve as building blocks for the construction of important heterocyclic frameworks such as pyrrolidines and γ-lactams.[2] These moieties also have potential applications in material science.[3] Consequently, the development of efficient synthetic methods to access these scaffolds is high in demand. Owing to the broad synthetic utility of 3-substituted succinimides and maleimides, several methods have been developed for their synthesis. 3-Arylsuccinimides are traditionally prepared by the ammonolysis of 3-arylsuccinic anhydrides at 180–210 °C.[4] However, the synthesis of 3-arylsuccinic anhydride is itself ponderous and only a few derivatives are commercially available. In 2010, Banwell reported a Pd-catalyzed Ullmann cross-coupling of o-nitrohaloarenes with bromomaleimide to deliver 3-arylsuccinimides in good to excellent yields.[5] Maleimides, a class of highly electrophilic olefins, are frequently utilized for introducing succinimide motifs into organic molecules by Michael addition.[6] Prabhu and co-workers reported conjugate addition of aryl ketones and amides to maleimides under ruthenium catalysis, using a stoichiometric amount of copper salt to promote the reaction.[7] The C–H activation strategy faces several disadvantages with conventional cross-coupling reactions, especially the need for pre-functionalization of starting materials, that is, synthesis of boronic acids, halides, triflates, etc.[8] Driller obtained 3,4-diethylsuccinimide by carbonylation of various terminal and internal alkynes with ammonia or amines using Fe3CO12 as catalyst.[9] Rhodium-catalyzed conjugate addition of arylboronic acid to maleimides provided 3-arylsuccinimides under microwave irradiation.[10] Catalytic hydroarylation of maleimides with different arenes would be a favorable route to achieve 3-arylsuccinimides. Michael addition of benzene with maleimides was targeted by Olah, but a large excess amount of catalyst was used.[11] In this context very recently, Li et al. reported HFIP-promoted Michael addition between N-methylmaleimides and anilines at higher temperatures to obtain 3-arylsuccinimides[12] (Scheme [1]).
However, the above methods have one or the other disadvantages such as low/moderate yields, complex manipulation, and unwanted side products. Most of the reactions usually demand high catalyst loadings, long reaction times, expensive and hazardous reagents and special reaction conditions to enhance the reactivity such as pre-functionalization of reactants,[8] high temperatures,[12] and microwave irradiation.[10] As a result, development of efficient, economical and environmentally benign approaches is highly desirable for this process. Friedel–Crafts (F–C) reaction plays an important role for the construction of C–C bond in many bioactive molecules.[13] Electron-rich arenes have been increasingly used by organic chemists as strong C(sp2)–H nucleophilic partners with electron-deficient alkenes due to their wide availability, strong electron-rich character, and unique regioselectivity.[14] Up to now, within the reach to literature and to the best of our knowledge, F–C reaction of electron-rich arenes with N-arylmaleimides is not known. In our work, directed towards the construction of 3-arylsuccinimide scaffold using the F–C strategy, we became intrigued by the idea of using inexpensive and green reagent methanesulfonic acid (MSA) under mild reaction conditions. MSA is considered readily biodegradable, ultimately forming sulfate and carbon dioxide, considered to be a natural product, and MSA is part of the natural sulfur cycle.[15]
In light of the important pharmaceutical implications of the unique structural motif of 3-arylsuccinimides and maleimides, herein we present an efficient, and novel F–C strategy between N-arylmaleimides and electron-rich arenes using MSA as a green catalyst. This reaction exhibits great reactivity, good substrate scope and site selectivity with high yields.
We began our optimization studies with N-phenylmaleimide (1a) and 1,3-dimethoxybenzene (2a) as model substrates. When the reaction of 1a and 2a was performed in the presence of BF3·OEt2 in DCM for 12 hours at room temperature, the 3-arylsuccinimide 5 was obtained in 49% yield (Table [1], entry 1). Encouraged by this result, we have tested other Lewis acids such as I2, SnCl4, ZnCl2, ZrCl4, and FeCl3 (Table [1]) in anticipating better yield of arylsuccinimide 5.
a Reaction conditions: N-Phenylmaleimide (1a; 0.5 mmol) and 1,3-dimethoxybenzene (2a; 0.5 mmol) in 3 mL of solvent at r.t.
b Isolated yields. NR: No reaction.
c Inseparable mixture was obtained.
d Reaction temperature is 60 °C.
e Reaction performed at 80 °C.
Unfortunately, among these tested Lewis acids, I2, FeCl3, ZnCl2, and ZrCl4 did not provide the product even in 12 hours and only the reactants were recovered (Table [1], entries 2–5). SnCl4 promoted the reaction and the product was obtained in marginally improved yield (entry 6). After investigating the effect of Lewis acids, we screened Brønsted acids to affect the reaction (entries 7–10). To our delight, methanesulfonic acid facilitated the reaction for rapid completion and gave the desired product in 4 hours in a good yield of 67% (entry 7).
Unfortunately, other Brønsted acids such as PTSA·H2O, TFA, and CF3SO3H did not induce the reaction (Table [1], entries 8–10). By these observations, methanesulfonic acid was found to be the optimal catalyst. After obtaining the best catalyst suited for this Friedel–Crafts reaction, we screened various solvents such as DCE, CH3CN, ethanol, methanol, and toluene for obtaining better conditions (Table [1]). Ethanol, methanol, and toluene were not found to be suitable for the transformation; only traces of the product 5 were obtained (entries 13–15). Reaction in acetonitrile afforded the arylsuccinimide 5 in 51% yield (entry 12). When the solvent was changed from CH3CN to halogenated solvents like CH2Cl2 and DCE, we found a moderate increase in the yield of the product (entries 7 and 11). The optimization conditions demonstrated that DCE was the optimal medium to afford the product in 75% yield.
Encouraged by this result we further decreased the amount of methanesulfonic acid from 100 mol% to 50 mol%; nevertheless, the yield of the product 5 was not altered (Table [1], entry 16). Further, lowering the amount of methanesulfonic acid to 25 mol% also did not mutate the reaction (entry 17). On raising the temperature from room temperature to 60 °C, the arylsuccinimide 5 was isolated in an increased yield of 80% (entry 18). Further increase in the reaction temperature, to 80 °C, did not show any improvement in the yields of the product 5 (entry 19). Thus, 25 mol% MeSO3H in DCE at 60°C was considered as the optimized reaction condition for the reaction.
After having the optimal conditions for this Friedel–Crafts reaction in hand, we explored the substrate scope of this reaction. In this regard, we first investigated the scope of electron-rich arenes 1,3-dimethoxybenzene (2a) and 1,3,5-trimethoxybenzene (2b) with N-arylmaleimide derivatives having different functionalities (Scheme [2]). All the reactions proceeded smoothly and demonstrated wide tolerance for diverse substituent on N-arylmaleimides to give the corresponding 3-arylsuccinimide 3–12 in very good yields under the same set of conditions. The N-aryl substituents on maleimide had very little influence on the yields. The arene moiety on maleimides 1b and 1c bearing electron-donating groups regardless of the position of the substituent, provided the products 3, 4, 7, and 8 in somewhat diminished yields. However, the N-arylmaleimide 1e possessing iodine as substituent on aromatic ring gave the products 11 and 12 in slightly increased yields. The parent N-arylmaleimide 1a provided the corresponding products 5 and 6 in very good yield of 80% and 91%, respectively. N-Arylmaleimide 1d bearing both electron-donating and electron-withdrawing group furnished the product 9 and 10 in 79% and 85% yield, respectively. It is notable that a given arylmaleimide, when participated in the reaction with 1,3,5-trimethoxybenzene (2b), provided 3-arylsuccinimide derivative in better yield in comparison to that with 1,3-dimethoxybenzene (2a). For instance, the product 4 derived from 2b was obtained in 85% yield, while the succinimide 3 derived from 2a was obtained in 75% yield. Also, the reactions of aryl maleimides with 2b are relatively faster (2 h) than those with 2a (3–4 h).
Notably, when para-position of the electron-rich arene was blocked, no substitution occurred at ortho-position presumably due to the strong steric effect. For instance, when 1,4-dimethoxybenzene (2c) and p-methoxyphenol (2d) were used as substrates at 80 °C, the corresponding products 13 and 14 were not obtained (Scheme [2]). Similarly, anisole, phenol, p-cresol, p-methoxyphenol, and 2,6-di-tert-butylphenol also did not afford the alkylated products at 80 °C, which may be attributed to the fact that these arenes are not nucleophilic enough under the reaction conditions to drive the reaction. Also, the arenes methyl benzoate, bromobenzene, 1-chloro-3,5-dimethoxybenzene, and 1-bromo-3,5-dimethoxybenzene did not participate in the addition reaction with N-phenylmaleimide even at 80 °C. The reactions of 1,2,3-trimethoxybenzene and guaiacol, under the optimized conditions, are not clean.
After successfully carrying out the Friedel–Crafts reaction of several N-arylmaleimides with 1,3-dimethoxybenzene and 1,3,5-trimethoxybenzene, we further demonstrated the efficacy of the current protocol by performing the reaction of N-arylmaleimides 1a–f with β-naphthol (2e) and resorcinol (2f) (Scheme [3]). The reaction of N-arylmaleimides 1a–f with β-naphthol and resorcinol proceeded smoothly under the optimized reaction conditions to provide the corresponding products 15–22 in very good to high yields. This trend was observed in the reaction N-arylmaleimides bearing electron-donating and electron-withdrawing groups. The reactions of N-arylmaleimides are faster with resorcinol. Furthermore, the yield in the reaction of a given N-arylmaleimide with resorcinol was found to be somewhat greater than that with β-naphthol. Methanesulfonic acid could not promote the reactions of 1-naphthol and 6-bromo-2-naphthol with N-phenylmaleimide at 80 °C.
Inspired by the current applicability of this F–C protocol we further explored the reaction of N-arylmaleimide 1d with the heteroarene N-methylindole (2e) and interestingly, the reaction proceeded very smoothly in 1.5 hours giving the indol-3-yl succinimide 23 in very high yield of 89% (Scheme [4]).
Further, to demonstrate the scalability of this F–C protocol to access 3-arylsuccinimides, we expanded the scale of 1a to 6.0 mmol (1.03 g) and finally obtained the target product 5 in 74% yield (1.38 g) (Scheme [5]).
The assigned structures of the products were based on the spectroscopic evidence such as 1H NMR (400 and 500 MHz), 13C NMR (100 and 125 MHz), and HRMS data. The structure of compound 10 was further confirmed from its single-crystal X-ray analysis[16] (Figure 2).
Based on the above results and previous literature reports,[17] a plausible reaction mechanism for the current F–C protocol is proposed as shown in Scheme [6]. Initially, methanesulfonic acid coordinates with the N-arylmaleimide and enhances the electrophilicity at α-carbon of the N-arylmaleimide and facilitates the attack of electron-rich arene at this position to generate the dearomatized intermediate A. The subsequent proton shift and aromatization of A affords the 3-arylsuccinimide.
In conclusion, we have presented a highly facile, metal-free and novel methanesulfonic acid catalyzed Friedel–Crafts protocol to access 3-arylsuccinimide derivatives with C(sp2)–H nucleophiles and N-arylmaleimide electrophiles, in very high yields under mild reaction conditions. The protocol is compatible with very nucleophilic substrates as electron-rich arenes. The readily available starting materials, mild reaction conditions, metal-free inexpensive catalysis, and broad substrate scope make this reaction valuable addition to the synthetic chemistry toolbox.
Unless otherwise noted, the chemicals were purchased from commercial suppliers at the highest purity grade available and were used without further purification. The maleimides 1a–f were synthesized by following the literature procedure. TLC was performed on pre-coated 0.25 mm silica gel plates (60F-254) using UV light as visualizing agent. Silica gel (100–200 mesh) was used for column chromatography. NMR spectra were recorded in CDCl3 and DMSO-d 6 using TMS as an internal standard on 400 MHz or 500 MHz instruments. Chemical shifts (δ) were reported as parts per million (ppm), relative to residual CHCl3 (7.26 ppm) or DMSO-d 6 (2.5 ppm) in the deuterated solvent or with TMS (δ = 0.00) as the internal standard.13C NMR spectra were referenced to CDCl3 (77.0 ppm, the middle peak) and DMSO-d 6 (δ = 39.5, the middle peak). Coupling constants (J) are expressed in hertz (Hz). Standard abbreviations were used to explain the multiplicities.
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3-Arylsuccinimides 3–23; General Procedure
To a stirred solution of the respective N-arylmaleimide[18] 1 (0.5 mmol) and an electron-rich arene 2 (0.5 mmol) in CH2Cl2 (3 mL) was added MsOH (0.012 g, 0.125 mmol) at r.t. The resulting mixture was then allowed to stir at 60 °C for 2–4 h. After completion of the reaction as shown by TLC, the reaction was quenched by adding sat. aq NaHCO3. The mixture was extracted with EtOAc (3 × 5 mL), and the combined organic layers were washed with H2O, dried (anhyd Na2SO4), and concentrated under reduced pressure. The crude reaction mixture was purified by column chromatography on silica gel (100–200 mesh) using EtOAc (5–30%) in hexanes as the eluent.
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3-(2,4-Dimethoxyphenyl)-1-(4-methoxyphenyl)pyrrolidine-2,5-dione (3)
White solid; yield: 127 mg (75%); mp 162–164 °C.
1H NMR (400 MHz, CDCl3): δ = 7.22 (d, J = 8.0 Hz, 2 H), 7.12 (d, J = 7.6 Hz, 2 H), 6.98 (d, J = 8.0 Hz, 2 H), 6.47 (s, 2 H), 3.97 (dd, J = 8.8, 4.4 Hz, 1 H), 3.81 (s, 3 H), 3.79 (s, 3 H), 3.77 (s, 3 H), 3.18 (dd, J = 18.0, 10.0 Hz, 1 H), 2.84 (dd, J = 18.0, 4.0 Hz, 1 H).
13C NMR (125 MHz, CDCl3): δ = 178.0, 176.2, 160.9, 59.4, 157.8, 131.4, 127.7, 125.1, 118.5, 114.5, 104.4, 99.3, 55.5, 55.4, 55.4, 43.6, 36.5.
HRMS (ESI+): m/z calcd for C19H19NO5Na [M + Na]+: 364.1155; found: 364.1152.
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1-(4-Methoxyphenyl)-3-(2,4,6-trimethoxyphenyl)pyrrolidine-2,5-dione (4)
White solid; yield: 149 mg (85%); mp 161–164 °C.
1H NMR (400 MHz, CDCl3): δ = 7.22 (d, J = 8.8 Hz, 2 H), 6.98 (d, J = 8.4 Hz, 2 H), 6.13 (d, J = 10.0 Hz, 2 H), 4.60 (dd, J = 9.2, 5.2 Hz, 1 H), 3.81 (s, 6 H), 3.80 (s, 3 H), 3.76 (s, 3 H), 3.14 (dd, J = 18.4, 10.0 Hz, 1 H), 2.74 (dd, J = 18.0, 4.8 Hz, 1 H).
13C NMR (125 MHz, CDCl3): δ = 178.9, 176.7, 161.0, 159.3, 158.7, 158.5, 127.7, 125.3, 114.5, 106.8, 91.0, 90.7, 56.2, 55.4, 35.4, 35.4.
HRMS (ESI+): m/z calcd for C20H21NO6Na [M + Na]+: 394.1261; found: 364.1264.
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3-(2,4-Dimethoxyphenyl)-1-phenylpyrrolidine-2,5-dione (5)
White solid; yield: 124 mg (80%); mp 136–139 °C.
1H NMR (400 MHz, CDCl3): δ = 7.49 (t, J = 8.0 Hz, 2 H), 7.40 (t, J = 6.8 Hz, 1 H), 7.33 (d, J = 8.0 Hz, 2 H), 7.13 (d, J = 7.6 Hz, 1 H), 6.49 (s, 1 H), 6.47 (d, J = 2.4 Hz, 1 H), 3.99 (dd, J = 9.6, 5.2 Hz, 1 H), 3.80 (s, 3 H), 3.78 (s, 3 H), 3.20 (dd, J = 18.0, 9.6 Hz, 1 H), 2.87 (dd, J = 18.4, 5.2 Hz, 1 H).
13C NMR (125 MHz, CDCl3): δ = 178.0, 176.0, 161.0, 157.7, 132.4, 131.4, 129.2, 128.5, 126.6, 118.3, 104.5, 99.6, 55.5, 55.4, 44.0, 36.4.
HRMS (ESI+): m/z calcd for C18H17NO4Na [M + Na]+: 334.1049; found: 334.1049.
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1-Phenyl-3-(2,4,6-trimethoxyphenyl)pyrrolidine-2,5-dione (6)
Brown solid; yield: 155 mg (91%); mp 141–143 °C.
1H NMR (400 MHz, CDCl3): δ = 7.47 (t, J = 7.2 Hz, 2 H), 7.38 (t, J = 7.2 Hz, 1 H), 7.32 (d, J = 7.2 Hz, 2 H), 6.14 (d, J = 10.0 Hz, 2 H), 4.63 (dd, J = 9.2, 5.2 Hz, 1 H), 3.82 (s, 3 H), 3.79 (s, 3 H), 3.76 (s, 3 H), 3.16 (dd, J = 10.0, 8.0 Hz, 1 H), 2.76 (dd, J = 18.4, 5.2 Hz, 1 H).
13C NMR (125 MHz, CDCl3): δ = 178.6, 176.4, 161.0, 158.7, 158.4, 132.8, 129.0, 128.3, 126.6, 107.5, 90.9, 55.8, 55.4, 55.4, 36.0, 35.4.
HRMS (ESI+): m/z calcd for C19H19NO5Na [M + Na]+: 364.1155; found: 364.1157.
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3-(2,4-Dimethoxyphenyl)-1-(3,5-dimethoxyphenyl)pyrrolidine-2,5-dione (7)
White solid; yield: 146 mg (79%); mp 160–162 °C.
1H NMR (400 MHz, CDCl3): δ = 7.37 (s, 1 H), 7.22 (d, J = 9.6 Hz, 1 H), 7.13 (d, J = 9.2 Hz, 1 H), 7.02 (d, J = 10.4 Hz, 1 H), 6.49 (s, 2 H), 3.94 (dd, J = 33.2, 20.4 Hz, 1 H), 3.90 (s, 3 H), 3.80 (s, 6 H), 3.19 (dd, J = 18.8, 10.4 Hz, 1 H), 2.86 (dd, J = 18.4, 3.6 Hz, 1 H).
13C NMR (125 MHz, CDCl3): δ = 178.0, 176.2, 160.9, 157.8, 149.3, 149.0, 131.4, 125.1, 119.1, 118.5, 111.2, 110.0, 104.5, 99.3, 56.2, 56.1, 56.0, 55.5, 43.1, 36.5.
HRMS (ESI+): m/z calcd for C20H21NO6Na [M + Na]+: 394.1261; found: 394.1260.
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1-(3,5-Dimethoxyphenyl)-3-(2,4,6-trimethoxyphenyl)pyrrolidine-2,5-dione (8)
White solid; yield: 166 mg (83%); mp 163–165 °C.
1H NMR (400 MHz, CDCl3 + DMSO-d 6): δ = 6.95 (d, J = 8.8 Hz, 1 H), 6.89 (d, J = 8.81 Hz, 1 H), 6.82 (s, 1 H), 6.15 (d, J = 10.0 Hz, 2 H), 4.62 (dd, J = 10.0, 5.6 Hz, 1 H), 3.90 (s, 3 H), 3.87 (s, 3 H), 3.83 (s, 3 H), 3.81 (s, 3 H), 3.78 (s, 3 H), 3.15 (dd, J = 18.0, 10.0 Hz, 1 H), 2.76 (dd, J = 18.0, 5.2 Hz, 1 H).
13C NMR (125 MHz, CDCl3): δ = 178.9, 176.6, 161.0, 158.7, 158.5, 149.2, 148.9, 125.4, 119.0, 111.2, 110.0, 106.8, 91.0, 90.8, 56.0, 55.9, 55.3, 36.0, 35.4.
HRMS (ESI+): m/z calcd for C21H23NO7Na [M + Na]+: 424.1366; found: 424.1364.
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1-(3-Chloro-4-methoxyphenyl)-3-(2,4-dimethoxyphenyl)pyrrolidine-2,5-dione (9)
White solid; yield: 148 mg (79%); mp 160–163 °C.
1H NMR (400 MHz, CDCl3): δ = 7.36 (s, 1 H), 7.21–7.10 (m, 2 H), 7.00 (d, J = 8.4 Hz, 1 H), 6.48 (s, 2 H), 3.96 (dd, J = 8.4, 4.0 Hz, 1 H), 3.91 (s, 3 H), 3.80 (s, 3 H), 3.80 (s, 3 H), 3.18 (dd, J = 17.2, 9.6 Hz, 1 H), 2.84 (dd, J = 18.0, 4.0 Hz, 1 H).
13C NMR (125 MHz, CDCl3): δ = 177.8, 175.8, 161.0, 157.7, 155.0, 131.6, 131.4, 128.5, 128.2, 126.0, 125.3, 122.8, 118.2, 112.0, 104.5, 99.6, 56.4, 55.6, 44.0, 36.9.
HRMS (ESI+): m/z calcd for C19H18ClNO5Na [M + Na]+: 398.0765; found: 398.0768.
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1-(3-Chloro-4-methoxyphenyl)-3-(2,4,6-trimethoxyphenyl)pyrrolidine-2,5-dione (10)
White solid; yield: 172 mg (85%); mp 160–163 °C.
1H NMR (400 MHz, CDCl3): δ = 7.36 (d, J = 2.4 Hz, 1 H), 7.22 (d, J = 2.0 Hz, 1 H), 7.19 (d, J = 2.0 Hz, 1 H), 7.01 (d, J = 8.8 Hz, 1 H), 6.14 (d, J = 10.0 Hz, 2 H), 4.62 (dd, J = 9.6, 5.2 Hz, 1 H), 3.91 (s, 3 H), 3.82 (s, 3 H), 3.80 (s, 3 H), 3.76 (s, 3 H), 3.15 (dd, J = 18.0, 9.6 Hz, 1 H), 2.75 (dd, J = 18.4, 5.2 Hz, 1 H).
13C NMR (125 MHz, CDCl3): δ = 178.6, 176.8, 161.0, 158.6, 158.4, 154.8, 128.8, 126.1, 125.3, 122.5, 112.0, 107.1, 90.9, 56.3, 55.8, 55.4, 35.9, 35.3.
HRMS (ESI+): m/z calcd for C20H20ClNO6Na [M + Na]+: 428.0871; found: 428.0876.
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3-(2,4-Dimethoxyphenyl)-1-(4-iodophenyl)pyrrolidine-2,5-dione (11)
White solid; yield: 190 mg (87%); mp 174–176 °C.
1H NMR (400 MHz, CDCl3): δ = 7.81 (d, J = 8.4 Hz, 2 H), 7.12 (t, J = 9.6 Hz, 3 H), 6.48–6.46 (m, 2 H), 4.00 (dd, J = 9.6, 5.2 Hz, 1 H), 3.80 (s, 3 H), 3.77 (s, 3 H), 3.20 (dd, J = 18.4, 10.0 Hz, 1 H), 2.87 (dd, J = 5.2, 18.4, 5.2 Hz, 1 H).
13C NMR (125 MHz, CDCl3): δ = 177.4, 175.5, 161.0, 157.8, 132.2, 131.6, 128.7, 118.3, 104.2, 99.3, 94.2, 55.6, 55.5, 43.7, 37.0.
HRMS (ESI+): m/z calcd for C18H16INO4Na [M + Na]+: 460.0016; found: 460.0019.
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1-(4-Iodophenyl)-3-(2,4,6-trimethoxyphenyl)pyrrolidine-2,5-dione (12)
White solid; yield: 207 mg (89%); mp 175–178 °C.
1H NMR (400 MHz, CDCl3): δ = 7.80 (d, J = 8.8 Hz, 2 H), 7.11 (d, J = 8.8 Hz, 2 H), 6.14 (d, J = 12.8 Hz, 2 H), 4.62 (dd, J = 10.0, 5.6 Hz, 1 H), 3.83 (s, 3 H), 3.81 (s, 3 H), 3.74 (s, 3 H), 3.16 (dd, J = 18.0, 10.0 Hz, 1 H), 2.75 (dd, J = 18.0, 5.2 Hz, 1 H).
13C NMR (125 MHz, CDCl3): δ = 178.4, 176.0, 161.1, 158.8, 158.4, 138.3, 132.5, 128.2, 128.1, 106.7, 93.9, 91.0, 90.8, 56.4, 55.8, 55.4, 36.0, 35.4.
HRMS (ESI+): m/z calcd for C19H18INO5Na [M + Na]+: 490.0121; found: 490.0101.
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3-(2-Hydroxynaphthalen-1-yl)-1-phenylpyrrolidine-2,5-dione (15)
White solid; yield: 123 mg (78%); mp 235–237 °C.
1H NMR (500 MHz, DMSO-d 6): δ = 10.42 (s, 1 H), 8.08 (d, J = 9.0 Hz, 1 H), 7.86 (d, J = 8.5 Hz, 1 H), 7.80 (d, J = 9.0 Hz, 2 H), 7.54 (d, J = 8.0 Hz, 3 H), 7.46 (d, J = 10.0 Hz, 1 H), 7.33 (d, J = 8.0 Hz, 2 H), 7.21 (d, J = 9.0 Hz, 1 H), 5.05 (dd, J = 7.5, 4.0 Hz, 1 H), 3.38 (dd, J = 18.0, 10.0 Hz, 1 H), 2.77 (dd, J = 18.5, 4.5 Hz, 1 H).
13C NMR (100 MHz, DMSO-d 6): δ = 178.7, 176.3, 152.9, 133.5, 133.2, 129.1, 129.1, 128.7, 128.3, 128.2, 127.1, 127.0, 122.8, 121.9, 118.0, 117.0, 38.0, 36.1.
HRMS (ESI+): m/z calcd for C20H15NO3K [M + K]+: 356.0683; found: 356.0684.
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3-(2,4-Dihydroxyphenyl)-1-phenylpyrrolidine-2,5-dione (16)
White solid; yield: 116 mg (82%); mp 201–203 °C.
1H NMR (500 MHz, DMSO-d 6): δ = 9.80 (s, 1 H), 9.32 (s, 1 H), 7.51 (t, J = 7.0 Hz, 2 H), 7.42 (t, J = 7.5 Hz, 1 H), 7.25 (d, J = 7.5 Hz, 2 H), 6.97 (d, J = 8.0 Hz, 1 H), 6.31 (s, 1 H), 6.21–6.20 (m, 1 H), 4.04 (dd, J = 9.5, 4.5 Hz, 1 H), 3.17 (dd, J = 18.0, 8.5 Hz, 1 H), 2.66 (dd, J = 18.0, 5.0 Hz, 1 H).
13C NMR (100 MHz, DMSO-d 6): δ = 178.5, 176.2, 158.0, 155.9, 133.2, 131.6, 129.0, 128.3, 127.1, 116.0, 106.2, 102.9, 43.1, 36.5.
HRMS (ESI+): m/z calcd for C16H13NO4K [M + K]+: 322.0476; found: 322.0475.
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3-(2-Hydroxynaphthalen-1-yl)-1-(4-methoxyphenyl)pyrrolidine-2,5-dione (17)
White solid; yield: 130 mg (75%); mp 246–249 °C.
1H NMR (500 MHz, DMSO-d 6): δ = 10.39 (s, 1 H), 8.07 (d, J = 98.5 Hz, 1 H), 7.85 (d, J = 8.0 Hz, 1 H), 7.79 (d, J = 9.0 Hz, 1 H), 7.52 (t, J = 7.5 Hz, 1 H), 7.34 (t, J = 7.5 Hz, 1 H), 7.24–7.19 (m, 3 H), 7.09 (d, J = 9.0 Hz, 2 H), 5.01 (dd, J = 9.5, 5.0 Hz, 1 H), 3.80 (s, 3 H), 3.35 (dd, J = 18.0, 10.0 Hz, 1 H), 2.74 (dd, J = 18.0, 5.0 Hz, 1 H).
13C NMR (100 MHz, DMSO-d 6): δ = 178.9, 176.5, 159.0, 152.9, 133.5, 129.1, 128.7, 128.3, 128.2, 126.9, 125.8, 122.8, 121.9, 118.1, 117.1, 55.5, 37.9, 36.0.
HRMS (ESI+): m/z calcd for C21H18NO4 [M + H]+: 348.1230; found: 348.1232.
#
3-(2,4-Dihydroxyphenyl)-1-(4-methoxyphenyl)pyrrolidine-2,5-dione (18)
White solid; 123 mg (79%); mp 249–251 °C.
1H NMR (500 MHz, DMSO-d 6): δ = 9.80 (s, 1 H), 9.34 (s, 1 H), 7.16 (d, J = 8.5 Hz, 2 H), 7.04 (d, J = 9.0 Hz, 2 H), 6.96 (d, J = 8.5 Hz, 1 H), 6.31 (s, 1 H), 6.21 (d, J = 7.0 Hz, 1 H), 4.01 (dd, J = 10.0, 5.0 Hz, 1 H), 3.78 (s, 3 H), 3.16 (dd, J = 18.0, 10.0 Hz, 1 H), 2.64 (dd, J = 17.5, 4.5 Hz, 1 H).
13C NMR (100 MHz, DMSO-d 6): δ = 178.8, 176.6, 159.0, 158.1, 156.0, 131.7, 128.4, 125.8, 116.1, 114.3, 106.2, 103.0, 55.5, 43.1, 36.5.
HRMS (ESI+): m/z calcd for C17H16NO5 [M + H]+: 314.1022; found: 314.1020.
#
1-(3-Chloro-4-methoxyphenyl)-3-(2-hydroxynaphthalen-1-yl)pyrrolidine-2,5-dione (19)
White solid; yield: 140 mg (74%); mp 223–225 °C.
1H NMR (500 MHz, DMSO-d 6): δ = 10.39 (s, 1 H), 8.05 (d, J = 8.5 Hz, 1 H), 7.85 (d, J = 8.0 Hz, 1 H), 7.79 (d, J = 9.0 Hz, 1 H), 7.53 (t, J = 7.0 Hz, 1 H), 7.36–7.27 (m, 4 H), 7.19 (d, J = 9.0 Hz, 1 H), 5.0 (dd, J = 9.5, 5.0 Hz, 1 H), 3.91 (s, 3 H), 3.35 (dd, J = 18.0, 8.0 Hz, 1 H), 2.73 (dd, J = 18.0, 5.0 Hz, 1 H).
13C NMR (100 MHz, DMSO-d 6): δ = 178.5, 176.2, 158.0, 155.9, 154.4, 131.6, 128.3, 127.2, 126.0, 120.8, 115.9, 114.6, 112.9, 106.2, 102.9, 56.5, 42.9, 36.4.
HRMS (ESI+): m/z calcd for C21H16ClNO4K [M + K]+: 420.0399; found: 420.0422.
#
1-(3-Chloro-4-methoxyphenyl)-3-(2,4-dihydroxyphenyl)pyrrolidine-2,5-dione (20)
White solid; yield: 138 mg (80%); mp 235–237 °C.
1H NMR (500 MHz, DMSO-d 6): δ = 9.80 (s, 1 H), 9.31 (s, 1 H), 7.30–7.27 (m, 2 H), 7.21 (dd, J = 9.0, 2.5 Hz, 1 H), 6.97 (d, J = 8.0 Hz, 1 H), 6.29 (d, J = 2.5 Hz, 1 H), 6.19 (dd, J = 8.0, 2.5 Hz, 1 H), 4.02 (dd, J = 9.5, 5.0 Hz, 1 H), 3.89 (s, 3 H), 3.17 (dd, J = 10.0, 8.0 Hz, 1 H), 2.62 (dd, J = 18.0, 5.0 Hz, 1 H).
13C NMR (100 MHz, DMSO-d 6): δ = 178.7, 176.2, 154.2, 152.8, 133.4, 129.2, 128.7, 128.2, 127.2, 127.0, 126.0, 122.8, 121.9, 120.9, 118.0, 117.0, 113.0, 56.5, 37.9, 36.0.
HRMS (ESI+): m/z calcd for C17H14ClNO5Na [M + Na]+: 370.0452; found: 370.0458.
#
1-(4-Chlorophenyl)-3-(2-hydroxynaphthalen-1-yl)pyrrolidine-2,5-dione (21)
White solid; yield: 140 mg (80%); mp 166–169 °C.
1H NMR (500 MHz, DMSO-d 6): δ = 10.39 (s, 1 H), 8.05 (d, J = 9.0 Hz, 1 H), 7.85 (d, J = 8 Hz, 1 H), 7.79 (d, J = 8.5 Hz, 1 H), 7.64–7.63 (m, 2 H), 7.53 (t, J = 7.5 Hz, 1 H), 7.38–7.33 (m, 3 H), 7.19 (d, J = 9.0 Hz, 1 H), 5.04 (dd, J = 9.5, 5.0 Hz, 1 H), 3.37 (d, J = 10.0 Hz, 1 H), 2.77 (dd, J = 18.0, 4.5 Hz, 1 H).
13C NMR (100 MHz, DMSO-d 6): δ = 178.9, 176.4, 153.3, 133.8, 133.2, 132.4, 129.6, 129.6, 129.5, 129.1, 128.5, 127.4, 123.2, 122.2, 118.4, 117.3, 38.4, 36.5.
HRMS (ESI+): m/z calcd for C20H14ClNO3K [M + K]+: 390.0293; found: 390.0292.
#
1-(4-Chlorophenyl)-3-(2,4-dihydroxyphenyl)pyrrolidine-2,5-dione (22)
White solid; yield: 133 mg (84%); mp 249–251 °C.
1H NMR (500 MHz, DMSO-d 6): δ = 9.83 (s, 1 H), 7.58 (d, J = 8.0 Hz, 2 H), 7.29 (d, J = 8.5 Hz, 2 H), 6.97 (d, J = 8.5 Hz, 1 H), 6.31 (s, 1 H), 6.21 (d, J = 8.5 Hz, 1 H), 4.04 (dd, J = 10.0, 4.5 Hz, 1 H), 3.18 (dd, J = 8.0, 4.4 Hz, 1 H), 2.66 (dd, J = 18.0, 5.0 Hz, 1 H).
13C NMR (100 MHz, DMSO-d 6): δ = 178.4, 176.1, 158.1, 156.0, 132.9, 132.0, 131.7, 129.2, 128.8, 115.9, 106.3, 103.0, 43.1, 36.5.
HRMS (ESI+): m/z calcd for C16H12ClNO4Na [M + Na]+: 340.0347; found: 340.0344.
#
1-(3-Chloro-4-methoxyphenyl)-3-(1-methyl-1H-indol-3-yl)pyrrolidine-2,5-dione (23)
Yellow solid; yield: 163 mg (89%); mp 166–169 °C.
1H NMR (400 MHz, CDCl3): δ = 7.50 (d, J = 10.0 Hz, 1 H), 7.41 (d, J = 2.5 Hz, 1 H), 7.35 (d, J = 10.5 Hz, 1 H), 7.30 (d, J = 9.0 Hz, 1 H), 7.24 (d, J = 3.0 Hz, 1 H), 7.16 (t, J = 9.5 Hz, 1 H), 7.10 (s, 1 H), 7.01 (d, J = 11.0 Hz, 1 H), 4.46 (dd, J = 12.0, 6.0 Hz, 1 H), 3.93 (s, 3 H), 3.79 (s, 3 H), 3.44 (dd, J = 18.8, 9.6 Hz, 1 H), 3.10 (dd, J = 18.8, 5.2 Hz, 1 H).
13C NMR (125 MHz, CDCl3): δ = 177.0, 175.4, 155.0, 137.3, 128.3, 128.2, 126.7, 126.0, 124.8, 122.7, 111.9, 109.6, 56.2, 38.2, 36.5, 32.7.
HRMS (ESI+): m/z calcd for C20H18ClN2O3 [M + H]+: 369.1000; found: 369.0990.
#
#
Acknowledgment
We gratefully acknowledge the DST for providing the HRMS facility in the FIST program. D.G. thanks DST India for research fellowship under inspire scheme.
Supporting Information
- Supporting information for this article is available online at https://doi-org.accesdistant.sorbonne-universite.fr/10.1055/s-0040-1706008.
- Supporting Information
-
References
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- 15 Baker SC, Kelly DP, Murrell JC. Nature 1991; 350: 627
- 16 CCDC 2007843 contains the supplementary crystallographic data for this paper. The
data can be obtained free of charge from The Cambridge Crystallographic Data Centre
via www.ccdc.cam.ac.uk/getstructures.
- 17a Motiwala HF, Vekariya RH, Aube J. Org. Lett. 2015; 17: 5484
- 17b Vekariya RH, Aube J. Org. Lett. 2016; 18: 3534
- 17c Ratnikov MO, Tumanov VV, Smit WA. Angew. Chem. Int. Ed. 2008; 47: 9739
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Corresponding Author
Publication History
Received: 17 September 2020
Accepted after revision: 09 December 2020
Article published online:
18 January 2021
© 2021. Thieme. All rights reserved
Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany
-
References
- 1a Porter RJ, Penry JK, Lacy JR, Newmark ME, Kupferberg HJ. Neurology 1979; 29: 1509
- 1b Nakamura N, Hirakawa A, Gao J, Kakuda H, Shiro M, Komatsu Y, Sheu C, Hattori M. J. Nat. Prod. 2004; 67: 46
- 1c Geethangili M, Tzeng Y. Evid. Based Complementary Altern. Med. 2011; 212641
- 1d Garad DN, Tanpure SD, Mhaske SB. Beilstein J. Org. Chem. 2015; 11: 1008
- 1e Han Z, Li P, Zhang Z, Chen C, Wang Q, Dong X.-Q, Zhang X. ACS Catal. 2016; 6: 6214
- 1f Kavitha K, Praveena KS. S, Ramarao EV. V. S, Murthy NY. S, Pal S. Curr. Org. Chem. 2016; 20: 1955
- 1g
Seiler MP,
Nozulak J.
WO EP861 20010126, 2001
- 2a Stewart SG, Ho LA, Polomska ME, Percival AT, Yeoh GC. ChemMedChem 2009; 4: 1657
- 2b Guan Q, Zuo D, Jiang N, Qi H, Zhai Y, Bai Z, Feng D, Yang L, Jiang M, Bao K, Li C, Wu Y, Zhang W. Bioorg. Med. Chem. Lett. 2015; 25: 631
- 2c Mandal A, Sahoo H, Dana S, Baidya M. Org. Lett. 2017; 19: 4138
- 3a Elduque X, Sanchez A, Sharma K, Pedroso E, Grandas A. Bioconjugate Chem. 2013; 24: 832
- 3b Fang Q, Wang J, Gu S, Kaspar RB, Zhuang Z, Zheng J, Guo H, Qiu S, Yan Y. J. Am. Chem. Soc. 2015; 137: 8352
- 4a Miller CA, Long LM. J. Am. Chem. Soc. 1951; 73: 4895
- 4b Miller CA, Scholl HI, Long LM. J. Am. Chem. Soc. 1951; 73: 5608
- 4c Daly MJ, Jones GW, Nicholls PJ, Smith HJ, Rowlands MG, Bunnett MA. J. Med. Chem. 1986; 29: 520
- 4d Kaminski K, Obniska J, Chlebek I, Wiklik B, Rzepka S. Bioorg. Med. Chem. 2013; 21: 6821
- 5 Banwell MG, Jones MT, Loong DT. J, Lupton DW, Pinkerton DM, Ray JK, Willis AC. Tetrahedron 2010; 66: 9252
- 6a Wrobel ZM, Chodkowski A, Herold F, Marciniak M, Dawidowski M, Siwek A, Starowicz G, Stachowicz K, Szewczyk B, Nowak G, Belka M, Baczek T, Satala G, Bozarski JA, Turlo J. Eur. J. Med. Chem. 2019; 183: 111736
- 6b An YL, Shao ZY, Cheng J, Zhao SY. Synthesis 2013; 45: 2719
- 6c An YL, Deng YL, Zhang W, Zhao SY. Synthesis 2015; 47: 1581
- 6d Yang Z, Zhu J, Wen C, Ge Y, Zhao S. Chin. J. Org. Chem. 2019; 39: 2412
- 7a Bettadapur KR, Lanke V, Prabhu KR. Org. Lett. 2015; 17: 4658
- 7b Lanke V, Bettadapur KR, Prabhu KR. Org. Lett. 2015; 17: 4662
- 7c Keshri P, Bettadapur KR, Lanke V, Prabhu KR. J. Org. Chem. 2016; 81: 6056
- 8a Bergman RG. Nature 2007; 446: 391
- 8b Lyons TW, Sanford MS. Chem. Rev. 2010; 110: 1147
- 8c Colby DA, Bergman RG, Ellman JA. Chem. Rev. 2010; 110: 624
- 8d Ackermann L. Chem. Rev. 2011; 111: 1315
- 8e Patureau FW, Wencel-Delord J, Glorius F. Aldrichimica Acta 2012; 45: 31
- 8f Song G, Wang F, Li X. Chem. Soc. Rev. 2012; 41: 3651
- 8g Liu C, Zhang H, Shi W, Lei A. Chem. Rev. 2011; 111: 1780
- 8h Giri R, Shi B.-F, Engle KM, Maugel N, Yu J.-Q. Chem. Soc. Rev. 2009; 38: 3242
- 8i Li B.-J, Shi Z.-J. Chem. Soc. Rev. 2012; 41: 5588
- 9 Driller KM, Klein H, Jackstell R, Beller M. Angew. Chem. Int. Ed. 2009; 48: 6041
- 10a Hayashi T, Shintani R, Duan WL. J. Am. Chem. Soc. 2006; 128: 5628
- 10b Iyer PS, O’Malley MM, Lucas MC. Tetrahedron Lett. 2007; 48: 4413
- 11 Koltunov KY, Prakash GK. S, Rasul G, Olah GA. Eur. J. Org. Chem. 2006; 4861
- 12 Li B, Mao Q, Zhou J, Liu F, Ye N. Org. Biomol. Chem. 2019; 17: 2242
- 13a Schafer G, Bode JW. Angew. Chem. Int. Ed. 2011; 50: 10913
- 13b Mori K, Wakazawa M, Akiyama T. Chem. Sci. 2014; 5: 1799
- 13c Wang YQ, Wei ZS, Zhu CQ, Ren YY, Wu C. Tetrahedron 2016; 72: 4643
- 14a Sharma N, Peddinti RK. J. Org. Chem. 2017; 82: 918
- 14b Sharma S, Parumala SK. R, Peddinti RK. J. Org. Chem. 2017; 82: 9367
- 15 Baker SC, Kelly DP, Murrell JC. Nature 1991; 350: 627
- 16 CCDC 2007843 contains the supplementary crystallographic data for this paper. The
data can be obtained free of charge from The Cambridge Crystallographic Data Centre
via www.ccdc.cam.ac.uk/getstructures.
- 17a Motiwala HF, Vekariya RH, Aube J. Org. Lett. 2015; 17: 5484
- 17b Vekariya RH, Aube J. Org. Lett. 2016; 18: 3534
- 17c Ratnikov MO, Tumanov VV, Smit WA. Angew. Chem. Int. Ed. 2008; 47: 9739
- 17d Tang R.-J, Milcent T, Crousse B. Eur. J. Org. Chem. 2017; 4753
- 18 Mandal R, Emayavaramban B, Sundararaju B. Org. Lett. 2018; 20: 2835
