Synfacts 2011(6): 0653-0653  
DOI: 10.1055/s-0030-1260362
Metal-Mediated Synthesis
© Georg Thieme Verlag Stuttgart ˙ New York

Ni-Catalyzed Alkyne Cycloaddition to Give Boronic Esters

Contributor(s):Paul Knochel, Andreas K. Steib
A.-L. Auvinet, J. P. A. Harrity*
University of Sheffield, UK
A Nickel-Catalyzed Benzannulation Approach to Aromatic Boronic Esters
Angew. Chem. Int. Ed.  2011,  50:  2769-2772  
Further Information

Publication History

Publication Date:
19 May 2011 (online)


Significance

A new nickel-catalyzed benzannulation of cyclobutenones with alkynylboronates to yield aromatic boronic esters has been disclosed. Furthermore, a one-pot cycloaddition-coupling protocol has been developed, whereby the nickel catalyst performs firstly the benzannulation and afterwards the cross-coupling.

Comment

Alkynylboronates bearing sp³-based substituents show high selectivity for isomer A, whereas those bearing sp²-based substituents mainly favor isomer B.