ChemInform Abstract: STEREOSPECIFIC ATTACK OF GRIGNARD REAGENTS ON OPTICALLY ACTIVE (INDAN-1-ONE)- AND (1-TETRALONE)-TRICARBONYL CHROMIUM DERIVATIVES, USE IN THE SYNTHESIS OF FREE OPTICALLY PURE TERTIARY ALCOHOLS

Arenesulfinyl chlorides react readily with 1,2:5,6-di-O-cyclohexylidene-α-D-glucofuranose in the presence of pyridine to afford the corresponding arenesulfinates. The ratio of diastereoisomeric sulfinates formed exceeds 2 : 1 with the major diastereoisomer possessing the (R)-configuration at sulfur. The diastereoisomeric esters are oils and were separable only in the case of the mesityl derivative when the crystalline, optically pure (R)-mesitylenesulfinic ester was isolated. Treatment of the diastereoisomeric sulfinates with Grignard reagents gives optically active sulfoxides in enantiomeric excess corresponding to the diastereoisomeric excess in the esters. Careful recrystallization of these optically impure sulfoxides leads to optically enriched products in favourable cases.

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Synthesis and resolution of an asymmetric arsonium cation. Crystal and molecular structures of (R)-Benzyl(methyl)(4-methylphenyl)(naphthalen-1-yl)- arsonium bromide and hexafluorophosphate

Australian Journal of Chemistry ◽

10.1071/ch9841171 ◽

1984 ◽

Vol 37 (6) ◽

pp. 1171 ◽

Cited By ~ 10

Author(s):

DG Allen ◽

CL Raston ◽

BW Skelton ◽

AH White ◽

SB Wild

Keyword(s):

Ion Exchange ◽

Absolute Configuration ◽

Optically Active ◽

Molecular Structures ◽

Orthorhombic Space Group ◽

Space Group ◽

X Ray ◽

Crystal And Molecular Structures ◽

Ion Exchange Column ◽

Optically Pure

The (�)-benzyl(methyl)(4-methylphenyl)(naphthalen-1-yl)arsonium cation has been synthesized and subsequently resolved by fractional crystallization of monohydrogen [R-(R*,R*)]-2,3-bis(benzoyloxy)- butanedioate salts. The separated diastereoisomers were converted into the corresponding optically active arsonium bromides by ion-exchange column chromatography. The absolute configuration of the arsonium cation exhibiting a positive rotation at 589 nm (sodium D line) has been established as (R) by single-crystal X-ray analysis of both the bromide and hexafluorophosphate salts. The arsonium bromide with [α]D + 54.8�(c, 0.62 in CH2Cl2) crystallizes in the orthorhombic space group P212121 (D24, No.19) with a 22.472(8), b 15.724(7), c 12.585(5) � and U 4447(3) �3. The corresponding hexafluorophosphate with [α]D + 19.3� (c, 0.5 in CH2Cl2) crystallizes in the same space group with a 23.56(2), b 16.40(1), c 13.12(1) � and U 5067(6) � 3. Benzylidene transfer to benzaldehyde from the arsonium ylide derived from either of the arsonium salts produced optically pure (–)-(S)-methyl(4-methylphenyl)(naphthalen-1-yl)arsine, [α]D - 115.9� (c, 0.593 in CHCl3), and partly resolved [R-(R*,R*)]-2,3-diphenyloxiran.

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Stereoselective Synthesis of Optically Active Diethanolamines Utilizing Diastereoselective Reaction of 1,3-Oxazolidines with Grignard Reagents

Heterocycles ◽

10.3987/com-95-7116 ◽

1995 ◽

Vol 41 (9) ◽

pp. 2007 ◽

Cited By ~ 8

Author(s):

Kimio Higashiyama ◽

Katuyuki Nakagawa ◽

Hiroshi Takahashi

Keyword(s):

Stereoselective Synthesis ◽

Optically Active ◽

Grignard Reagents ◽

Diastereoselective Reaction

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Use of Menthyl 2-Methoxynaphthalene-1-sulfinates in the Andersen Synthesis of Optically Active Sulfoxides. Facile Cleavage by Grignard Reagents of Some Aromatic Methyl Ethers

Australian Journal of Chemistry ◽

10.1071/ch9941925 ◽

1994 ◽

Vol 47 (10) ◽

pp. 1925 ◽

Cited By ~ 4

Author(s):

KH Bell ◽

LF Mccaffery

Keyword(s):

Grignard Reagent ◽

Methoxy Group ◽

Optically Active ◽

Grignard Reagents ◽

Sulfinyl Group

The pure crystalline diastereomers (1R,2S,5R)-menthyl (R)- and (S)-2-methoxynaphthalene-1-sulfinate (1b) have been prepared and, by reaction with Grignard reagents (the Andersen procedure), converted into optically active alkyl and aryl 2-methoxynaphthyl sulfoxides in 67-77% yields. Use of an excess of Grignard reagent results in facile O-alkyl cleavage of the methoxy group to the corresponding naphthol or a competing loss of the alkyl- or aryl- sulfinyl group to form 2-methoxynaphthalene. Pure diastereomers of menthyl 2,7- dimethoxynaphthalene-1-sulfinate (2b) and menthyl 4-methoxynaphthalene-1-sulfinate (3b) have also been prepared and their reactions with Grignard reagents have been studied.

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