Conversion of L-rhamnose and D-mannitol into the enantiomeric acetyl-α- and -β-methylcholines
作者:T.D. Inch、G.J. Lewis
DOI:10.1016/s0008-6215(00)81182-9
日期:1971.2
One-Pot Generation and Conversion of Trichloroacetimidates for the Racemization-Free Allylation and Benzylation of α-Hydroxyesters and the Enantiopure Synthesis of a Chiral Diglycole
O-Allylations and O-benzylations of alpha -hydroxy esters (3a-3c) are performed without racemization. The reagents applied, O-allyl- and O-benzyltrichloroacetimidate (5a, 5b) are prepared and converted in a one-pot-procedure. After protection by benzylation (S)-(-)-ethyl lactate (3a) is converted by a sequence of carbonyl reduction, alcohol activation, ether formation, and deprotection to the optically active diglycole derivative 1a.
Synthesis of a new asymmetric cyclopentadienyl ligand: Application to the preparation of a trivalent samarium complex
作者:P. Van de Weghe、C. Bied、J. Collin、J. Marçalo、I. Santos
DOI:10.1016/0022-328x(94)84014-8
日期:1994.7
A short synthesis of a new asymmetric cyclopentadienyl ligand 2 (Cp'H) substituted by a benzyl ether group in the beta position on the side chain of the ring is described. Reaction of its potassium salt with samarium triiodide leads to the isolation of a trivalent samarium complex Cp'2SmI.