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Allyl transfer to aldehydes and ketones by Bronsted acid activation of allyl and crotyl 1,3,2-dioxazaborolidines.

ABSTRACT: Alkyl dioxazaborolidines are air-stable and often crystalline organoboranes. A variety of Brønsted acids activate allyl dioxazaborolidines to generate reactive allyl-transfer reagents in situ. These reagents add to aldehydes and ketones to generate the corresponding alcohols in good yields under mild conditions. The E- and Z-crotyl reagents react diastereoselectively with aldehydes and ketones to produce anti and syn adducts, respectively, a result consistent with a cyclic transition state (type I mechanism).

SUBMITTER: Reilly MK

PROVIDER: S-EPMC3017000 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Allyl transfer to aldehydes and ketones by Brønsted acid activation of allyl and crotyl 1,3,2-dioxazaborolidines.

Reilly Maureen K MK Rychnovsky Scott D SD

Organic letters 20101101 21

Alkyl dioxazaborolidines are air-stable and often crystalline organoboranes. A variety of Brønsted acids activate allyl dioxazaborolidines to generate reactive allyl-transfer reagents in situ. These reagents add to aldehydes and ketones to generate the corresponding alcohols in good yields under mild conditions. The E- and Z-crotyl reagents react diastereoselectively with aldehydes and ketones to produce anti and syn adducts, respectively, a result consistent with a cyclic transition state (type ...[more]

PMID: 20942379

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