ISSN:
1434-193X
Keywords:
C, C Coupling reactions, Pd-catalyzed
;
Eliminations, stereoselective β
;
Enol triflates
;
Lactones
;
Olefins, stereoselective synthesis of
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A novel strategy for the stereoselective synthesis of E- or Z-configured γ-alkylidenebutenolides was applied to the preparation of the model compounds 6/7 (E) and 8/9 (Z) of the antibiotics tetrenolin (E) and lissoclinolide (Z), respectively. For introducing the α-substituents of the target molecules the butenolide triflates ul- and lk-16 were subjected to Stille couplings with trans-Bu3Sn-CH=CH-CH2-OH or trans,trans-Bu3Sn-CH=CH-CH=CH-CH2-OH (room temp., 10 min). Acetonide cleavages and bis(tert-butyldimethylsilylations) set the stage for introducing the Cexocyclic=Cγ bonds through anti-selective (ds = 96:4-99:1) eliminations of triflic acid (ul-21→E-23, lk-21→Z-23, ul-22→E-24, lk-22→Z-24).
Type of Medium:
Electronic Resource
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