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Diastereoselectivity in the directed aldol condensation of 2-trimethylsiloxyfuran with aldehydes. A stereodivergent route to threo and erythro δ-hydroxy-γ-lactones

✍ Scribed by Charles W. Jefford; Danielle Jaggi; John Boukouvalas


Publisher
Elsevier Science
Year
1987
Tongue
French
Weight
247 KB
Volume
28
Category
Article
ISSN
0040-4039

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✦ Synopsis


Threo and erythro-6-hydroxy-a,fi-unsaturated -y-lactones are obtained with useful diastereoselection by condensing 2-trimethylsiloxyfuran and aldehydes by varying the reaction reaction conditions.

A stereomechanistic rationale is presented together with a practical two-step synthesis of the threo and erythro 5-hydroxy-4-decanolides (L factors).

Recent reports on 2-trimethylsiloxyfuran (1) show that it has promise as a masked butenolide.lm4 However, in order to exploit 1 in synthesis, the appropriate conditions need to be found for controlling the regio-and diastereoselectivity of carbon-carbon bond formation.

Described herein are results of a systematic investigation of the reaction of 1 with aldehydes which demonstrate for the first time how useful diastereoselection can be achieved at will for obtaining predominantly either threo (2) or erythro (4) 6-hydroxy-a,j3-unsaturated-ylactones.