Asymmetric Michael Additions via SAMP‐/RAMP‐Hydrazones Enantioselective Synthesis of β‐Substituted Δ‐Oxopentanoates and δ‐Lactones1)
- 1 July 1987
- journal article
- research article
- Published by Wiley in European Journal of Inorganic Chemistry
- Vol. 120 (7) , 1223-1227
- https://doi.org/10.1002/cber.19871200718
Abstract
Asymmetric Michael addition of metalated acetaldehyde SAMP‐ or RAMP‐hydrazone (S)‐ or (R)‐2 to α,β‐unsaturated esters 3 and subsequent oxidative cleavage by ozonolysis yields the β‐substituted δ‐oxopentanoates (R)‐ or (S)‐5 with high enantiomeric excesses (ee = 90 to ≧ 96%). Racemization‐free reduction and cyclization affords the corresponding optically active δ‐lactones (R)‐ or (S)‐7.This publication has 14 references indexed in Scilit:
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