5398-11-8Relevant articles and documents
Catalytic enantioselective synthesis of chiral phthalides by Sml 2-mediated reductive cyclization of 2-acylarylcarboxylates
Huang, Ling-Lin,Xu, Ming-Hua,Lin, Guo-Qiang
, p. 5624 - 5625 (2006)
A significant new and efficient catalytic asymmetric approach for the highly enantioselective synthesis of chiral phthalides by SmI2-induced reductive cyclization of 2-acylarylcarbonylates was developed. The combination of (4S,5R)-4,5-diphenyloxazolidin-2-one and 2,2,6,6-tetramethylpiperidine was found to be a very effective catalyst system in the reaction. This method provides a ready access to a broad range of enantiomerically enriched phthalides (up to 99% ee). Copyright
An efficient direct asymmetric synthesis of 3-substituted phthalides
Zhang, Zhan-Bin,Lu, Yong-Qin,Duan, Xin-Fang
, p. 3435 - 3438 (2011)
A facile, two-step, asymmetric synthesis of 3-substituted phthalides has been developed. The enantiopure amide, obtained through coupling of 2-iodobenzoic acid with (S)-1-(pyrrolidin-2-ylmethyl)-1H-imidazole, was magnesiated using isopropylmagnesium chloride. Corresponding reactions with a range of aldehydes were carried out in situ by either direct addition or transmetallation using zinc(II) chloride. Intramolecular esterification of the adduct allowed the versatile asymmetric synthesis of phthalides in up to 88% enantiomeric excess. Georg Thieme Verlag Stuttgart.
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Lansbury,Peterson
, p. 3537 (1961)
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Stereoselective synthesis of 3-substituted phtalides via asymmetric transfer hydrogenation using well-defined ruthenium catalysts under neutral conditions
Everaere, Kathelyne,Scheffler, Jean-Luc,Mortreux, André,Carpentier, Jean-Fran?ois
, p. 1899 - 1901 (2001)
The asymmetric transfer hydrogenation of methyl 2-acylbenzoates and 2-propyl 3-acetylpyridine-2-carboxylate in 2-propanol, in the absence of base, with presynthesized Ru-{β-amino alcohol} or Ru-{TsDPEN} true catalysts provides 3-alkylphtalides in high yields and 92-97% ee. The procedure is, however, not as efficient for the preparation of optically active 3-phenylphtalide.
Access to Diarylmethanols by Wittig Rearrangement of ortho-, meta-, and para-Benzyloxy- N-Butylbenzamides
Aitken, R. Alan,Harper, Andrew D.,Inwood, Ryan A.,Slawin, Alexandra M. Z.
supporting information, p. 4692 - 4701 (2022/04/07)
The N-butyl amide group, CONHBu, has been found to be an effective promoter of the [1,2]-Wittig rearrangement of aryl benzyl ethers and thus allow the two-step synthesis of isomerically pure substituted diarylmethanols starting from simple hydroxybenzoic acid derivatives. The method is compatible with a wide range of functional groups including methyl, methoxy, and fluoro, although not with nitro and, unexpectedly, is applicable to meta as well as ortho and para isomeric series.
Visible Light-Promoted Magnesium, Iron, and Nickel Catalysis Enabling C(sp3)-H Lactonization of 2-Alkylbenzoic Acids
Li, Sasa,Su, Mincong,Sun, Jie,Hu, Kunjun,Jin, Jian
supporting information, p. 5842 - 5847 (2021/07/31)
A mild and practical C(sp3)-H lactonization protocol has been achieved by merging photocatalysis and magnesium (iron, nickel) catalysis. A diverse range of 2-alkylbenzoic acids with a variety of substitution patterns could be transformed into the corresponding phthalide products. Based on the mechanistic experimentation and reported prior studies, a possible mechanism for the benzylic oxidative lactonization reaction was proposed with the hypothetic photoactive ternary complex formed between the 2-alkylbenzoic acid substrate, magnesium ion, and bromate anion.
Binaphthyl-prolinol chiral ligands: Design and their application in enantioselective arylation of aromatic aldehydes
Yao, Chao,Chen, Yaoqi,Sun, Ruize,Wang, Chao,Huang, Yue,Li, Lin,Li, Yue-Ming
supporting information, p. 3644 - 3655 (2021/05/04)
Binaphthyl-prolinol ligands were designed and applied in enantioselective arylation of aromatic aldehydes and sequential arylation-lactonization of methyl 2-formylbenzoate. Under optimized conditions, the reactions provided the desired diarylmethanols and 3-aryl phthalides in up to 96% yields with up to 99% ee and up to 89% yields with up to 99% ee, respectively. In particular, essentially optically pure 3-aryl phthalides (over 99% ee) were obtained in large quantities through recrystallization. This journal is