Asymmetric Hydroformylation of <i>Z</i>-Enamides and Enol Esters with Rhodium-Bisdiazaphos Catalysts
作者:M. Leigh Abrams、Floriana Foarta、Clark R. Landis
DOI:10.1021/ja507701k
日期:2014.10.15
Asymmetric hydroformylation (AHF) of Z-enamides and Z-enol esters provides chiral, alpha-functionalized aldehydes with high selectivity and atom economy. Rh-bisdiazaphospholane catalysts enable hydroformylation of these challenging disubstituted substrates under mild reaction conditions and low catalyst loadings. The synthesis of a protected analog of l-DOPA demonstrates the utility of AHF for enantioselective
Synthesis of (2E,4E)-dienals by double formyl-olefination with an arsonium salt and its application in the syntheses of lipoxygenase metabolites of arachidonic acid
A new facile route to (2E,4E)-dienals by a double formyl-olefination with arsoniumsalts has been developed. By this method and with other arsonium reagents in the key step some lipoxygenase metabolites of arachidonic acid, lipoxin A4 and B4 and leukotriene B4, have been synthesized.
Facile approach towards the synthesis of homochiral functionalised alcohols from 4-O-[(tert)-butyldimethylsilyl]-2,3-O-cyclohexylidene-l-threose of (l)-(+)-tartaric acid origin
作者:Angshuman Chattopadhyay、Bhaskar Dhotare
DOI:10.1016/s0957-4166(98)00282-1
日期:1998.8
(l)-(+)-Diethyl tartarate 2 has been transformed into the aldehyde 6. Grignard additions to 6 take place with moderate diastereoselectivity giving predominant formation of the anti products 8a–e. However, in each case the diastereoalcohols are easily separable by column chromatography giving rise to the formation of a series of functionalised homochiral alcohols 7 and 8. On the other hand Zn mediated allylation
A practical preparation of α-hydroxy and α,β-dihydroxy aldehydes, useful intermediates for the synthesis of arachidonic acid metabolites, starting with<scp>D</scp>-glyceraldehyde acetonide
作者:Sentaro Okamoto、Toshiyuki Shimazaki、Yasunori Kitano、Yuichi Kobayashi、Fumie Sato
DOI:10.1039/c39860001352
日期:——
Optically active α-hydroxy and α,β-dihydroxyaldehydes, usefulintermediates for synthesis of lipoxygenase metabolites of arachidonicacid, are synthesized highly diastereoselectively starting with readily available D-glyceraldehyde acetonide.
(R)-2,3-O-Cyclohexylideneglyceraldehyde, a Versatile Intermediate for Asymmetric Synthesis of Chiral Alcohol
作者:A. Chattopadhyay、V. R. Mamdapur
DOI:10.1021/jo00108a020
日期:1995.2
Grignard addition to (R)-2,3-O-cyclohexylideneglyceraldehyde (IIa) gave rise to column chromatographically separable diastereo alcohols 2 and 3 including highly functionalized and synthetically exploitable homoallylic alcohols 2e and 3e and homopropargylic alcohols 2f and 3f. Compound 3c on functional manipulation gave rise to (-)-coriolic acid synthon 6.