(2S, 3R)-2-acetooxymethanyl-3-(P-nitrophenyl)-N-tosylaziridine 5 was synthesized from (1S, 2S)-2-amino-1-(4-nitrophenyl)-1, 3-propanediol 1 in four steps with a 24.8% overall yield. This reaction is stereospecific and...(2S, 3R)-2-acetooxymethanyl-3-(P-nitrophenyl)-N-tosylaziridine 5 was synthesized from (1S, 2S)-2-amino-1-(4-nitrophenyl)-1, 3-propanediol 1 in four steps with a 24.8% overall yield. This reaction is stereospecific and occurs an expectable configuration inversion at α-carbon atom of benzyl group. The structure of substituted aziridine was determined on FT-IR, NMR, MS and so on.展开更多
The recent methods of resolution, enantiomeric excess determination and synthesis of optically active alcohols from asymmetric reduction of prochiral ketones are reviewed in the article with references. Important func...The recent methods of resolution, enantiomeric excess determination and synthesis of optically active alcohols from asymmetric reduction of prochiral ketones are reviewed in the article with references. Important functions and applications of optically active alcohols in biological and chemical research area are described in an introduction part. The following part deals with resolution and enantiomeric excess determination of racemic alcohols. The next part discusses asymmetric reduction of prochiral ketone and related compounds, which including: (a) Reduction by chirally modified aluminum and boron hydrides; (b) Catalytic reduction with chiral transition metal complexes; (c) Enantioselective reduction by hydride transfer from carbon; (d) Biocatalytic reduction; (e) Asymmetric synthesis of chiral nonracemic alcohols with help of physical methods. A conclusion about optically active alcohols from asymmetric reduction of ketones followes in the final part of article.展开更多
The hydrolysis reaction of (±)-2-acetamido-3-hydroxy-1-(4-nitrophenyl)-1-propanone[(±)-[STHZ]1], an intermediate of chloramphenicol, was studied and three different products were obtained respectively under ...The hydrolysis reaction of (±)-2-acetamido-3-hydroxy-1-(4-nitrophenyl)-1-propanone[(±)-[STHZ]1], an intermediate of chloramphenicol, was studied and three different products were obtained respectively under different reaction conditions. The resolution of hydrolysis product (±)-2-amino-3-hydroxy- 1-(4-nitrophenyl)-1-propanone, an intermediate of chloramphenicol, was studied and three different products were obtained respectively under different reaction conditions. The resolution of hydrolysis product (±)-2-amino-3-hydroxy- 1-(4-nitrophenyl)-1-propanone[(±)-[STHZ]3] was carried out. A process of crystallization-induced asymmetric transformation was observed and up to 76% of the optically pure enantiomer was obtained in the resolution of (±)- was carried out. A process of crystallization-induced asymmetric transformation was observed and up to 76% of the optically pure enantiomer was obtained in the resolution of (±)-3.展开更多
The present paper covers the simply and highly stereoselective syntheses of (α-S, 4S)-2-dichloromethyl-4, 5-dihydro-α-(4-nitrophenyl)-4-oxazolemethanol (4a), (α-S, 4S)-2-methyl-4, 5-dihydro-α-(4-nitrophenyl)-4-oxa...The present paper covers the simply and highly stereoselective syntheses of (α-S, 4S)-2-dichloromethyl-4, 5-dihydro-α-(4-nitrophenyl)-4-oxazolemethanol (4a), (α-S, 4S)-2-methyl-4, 5-dihydro-α-(4-nitrophenyl)-4-oxazolemethanol (4b), and (α-R, 4R)-2-dichloromethyl-4, 5-dihydro-α-[(4-methylsulfonyl)phenyl]-4-oxazolemethanol(4c) with good yields(80%—90%). A configuration inversion product, (1R, 2S)-2-dichloroacetamido-1-(4-nitrophenyl)-1, 3-propanediol (8), was obtained during our attempting to convert compound 4a into (4S, 5R)-2-(dichloromethyl)-4, 5-dihydro-5-(4-nitrophenyl)-4-oxazolemethanol(7).展开更多
基金Supported by the science and technology fund of Wuhan city (No:996 0 0 10 16 G)
文摘(2S, 3R)-2-acetooxymethanyl-3-(P-nitrophenyl)-N-tosylaziridine 5 was synthesized from (1S, 2S)-2-amino-1-(4-nitrophenyl)-1, 3-propanediol 1 in four steps with a 24.8% overall yield. This reaction is stereospecific and occurs an expectable configuration inversion at α-carbon atom of benzyl group. The structure of substituted aziridine was determined on FT-IR, NMR, MS and so on.
文摘The recent methods of resolution, enantiomeric excess determination and synthesis of optically active alcohols from asymmetric reduction of prochiral ketones are reviewed in the article with references. Important functions and applications of optically active alcohols in biological and chemical research area are described in an introduction part. The following part deals with resolution and enantiomeric excess determination of racemic alcohols. The next part discusses asymmetric reduction of prochiral ketone and related compounds, which including: (a) Reduction by chirally modified aluminum and boron hydrides; (b) Catalytic reduction with chiral transition metal complexes; (c) Enantioselective reduction by hydride transfer from carbon; (d) Biocatalytic reduction; (e) Asymmetric synthesis of chiral nonracemic alcohols with help of physical methods. A conclusion about optically active alcohols from asymmetric reduction of ketones followes in the final part of article.
基金Supported by the Science and Technology Fund of Wuhan City( No.9960 0 10 16G)
文摘The hydrolysis reaction of (±)-2-acetamido-3-hydroxy-1-(4-nitrophenyl)-1-propanone[(±)-[STHZ]1], an intermediate of chloramphenicol, was studied and three different products were obtained respectively under different reaction conditions. The resolution of hydrolysis product (±)-2-amino-3-hydroxy- 1-(4-nitrophenyl)-1-propanone, an intermediate of chloramphenicol, was studied and three different products were obtained respectively under different reaction conditions. The resolution of hydrolysis product (±)-2-amino-3-hydroxy- 1-(4-nitrophenyl)-1-propanone[(±)-[STHZ]3] was carried out. A process of crystallization-induced asymmetric transformation was observed and up to 76% of the optically pure enantiomer was obtained in the resolution of (±)- was carried out. A process of crystallization-induced asymmetric transformation was observed and up to 76% of the optically pure enantiomer was obtained in the resolution of (±)-3.
基金Supported by the Science and Technology Fundation of Wuhan City and Wuhan Red Heart K(Group) Co. Ltd.
文摘The present paper covers the simply and highly stereoselective syntheses of (α-S, 4S)-2-dichloromethyl-4, 5-dihydro-α-(4-nitrophenyl)-4-oxazolemethanol (4a), (α-S, 4S)-2-methyl-4, 5-dihydro-α-(4-nitrophenyl)-4-oxazolemethanol (4b), and (α-R, 4R)-2-dichloromethyl-4, 5-dihydro-α-[(4-methylsulfonyl)phenyl]-4-oxazolemethanol(4c) with good yields(80%—90%). A configuration inversion product, (1R, 2S)-2-dichloroacetamido-1-(4-nitrophenyl)-1, 3-propanediol (8), was obtained during our attempting to convert compound 4a into (4S, 5R)-2-(dichloromethyl)-4, 5-dihydro-5-(4-nitrophenyl)-4-oxazolemethanol(7).
