Generation of 1,2-azaboretidines Reduction of ADC Borane Adducts

Overview

Journal Chem Sci

Publisher Royal Society of Chemistry

Specialty Chemistry

Date 2017 Jul 15

PMID 28706706

Citations 1

Authors

H Braunschweig

A Gackstatter

T Kupfer

T Scheller

F Hupp

A Damme

N Arnold

W C Ewing

Affiliations

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Abstract

Reaction of the acyclic (diamino)carbene (ADC) :C(NiPr) () with different dihaloboranes of the type RBX (R = Mes, Dur; X = Cl, Br) smoothly afforded a novel class of ADC-stabilized borane adducts. For MesBBr however, the reaction did not stop at the adduct level, but an uncommon rearrangement process occurred, which eventually resulted in the formation of a 5-membered boracycle after elimination of mesitylene. Chemical reduction of the ADC borane adducts by KC selectively yielded air stable 1,2-azaboretidines. Detailed DFT studies suggest a reduction mechanism involving a highly reactive borylene intermediate, which is converted into the boracycles a rearrangement/C-H activation sequence.

Citing Articles

The Dewar Isomer of 1,2-Dihydro-1,2-azaborinines: Isolation, Fragmentation, and Energy Storage.

Edel K, Yang X, Ishibashi J, Lamm A, Maichle-Mossmer C, Giustra Z Angew Chem Int Ed Engl. 2018; 57(19):5296-5300.

PMID: 29457683 PMC: 6214188. DOI: 10.1002/anie.201712683.

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