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Updated: Mar 21, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
PNPCB heterocycles via thermal and Lewis acid catalyzed trans-hydroborations
Louie Fan1, Douglas W Stephan1
1Department of Chemistry, University of Toronto, 80 St George St, Toronto, Ontario M5S 3H6, USA. dstephan@chem.utoronto.ca.
Abstract:
The compounds iPr2P(BH3)N3, tBu2PC[triple bond, length as m-dash]CR (R = Ph , tBu , Cy ) and Ph2PC[triple bond, length as m-dash]CR (R = Ph , tBu , Cy ) were reacted to give the products tBu2P(C[triple bond, length as m-dash]CR)NP(BH3)iPr2 (R = Ph , tBu , Cy ) and Ph2P(C[triple bond, length as m-dash]CR)NP(BH3)iPr2 (R = Ph , tBu , Cy ). Subsequent thermally induced or Lewis acid catalyzed intramolecular hydroboration of and afforded the PNPCB heterocyclic compounds Ph2P(C[double bond, length as m-dash]CHPh)NP(BH2)iPr2 and tBu2P(C[double bond, length as m-dash]CHPh)NP(BH2)iPr2, respectively. Compounds and were crystallographically characterized and the mechanisms and implications for the synthesis of inorganic heterocycles are considered.
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