Amide-Forming Ligation of Acyltrifluoroborates and Hydroxylamines in Water
作者:Aaron M. Dumas、Gary A. Molander、Jeffrey W. Bode
DOI:10.1002/anie.201201077
日期:2012.6.4
Come together, right now: Acyltrifluoroborates and O‐benzoyl hydroxylamines come together to form amides in water (see scheme). The ligations are complete within minutes at room temperature and do not require any reagents or catalysts. The reaction has a broad substrate scope and tolerates unprotected functional groups.
Acylboranes are among the most elusive boron-containing organic functional groups, a fact that has impeded development of new reactions employing them as substrates. A new synthesis of acyltrifluoroborates from benzotriazole (Bt)-based N,O-acetals has been developed. Two other routes provide acyltrifluoroborates containing alcohols, aldehydes, and carbamates. The ketone-like reactivity of the acyltrifluoroborate functional group is demonstrated, and the first X-ray structure of an acyltrifluoroborate is reported.