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Updated: Jan 2, 2026

Synthesis of 1,2-Azaborines and the Preparation of Their Protein Complexes with T4 Lysozyme Mutants
Published on: March 25, 2017
Synthesis and Homologation of an Azetidin-2-yl Boronic Ester with α-Lithioalkyl Triisopropylbenzoates
Pascal K Delany1, David M Hodgson1
1Department of Chemistry, Chemistry Research Laboratory , University of Oxford , Mansfield Road , Oxford OX1 3TA , U.K.
Abstract:
An α-boryl azetidine, obtained by α-lithiation-borylation of N-Botc azetidine, undergoes reaction with α-triisopropylbenzoyloxy organolithiums to give homologated boronic esters that can be further oxidized, homologated, arylated, and deprotected to give a range of α-substituted azetidines. Scalemic α-boryl azetidine-α-triisopropylbenzoyloxy organolithium pairings show stereospecific reagent control, providing access to either diastereomeric series of homologated boronic esters with very high er's.
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