Synthesis 2018; 50(17): 3420-3429
DOI: 10.1055/s-0036-1591594
© Georg Thieme Verlag Stuttgart · New York

Iridium-Catalysed C–H Borylation of 2-Pyridones; Bisfunctionalisation of CC4

Aurélien Honraedt
a  School of Chemistry, University of Bristol, BS8 1TS, Bristol, UK   Email:   Email:
Worawat Niwetmarin
a  School of Chemistry, University of Bristol, BS8 1TS, Bristol, UK   Email:   Email:
Cecilia Gotti
b  CNR, Institute of Neuroscience, Biometra Department, University of Milan, 20129 Milan, Italy
Hugo Rego Campello*
a  School of Chemistry, University of Bristol, BS8 1TS, Bristol, UK   Email:   Email:
Timothy Gallagher*
a  School of Chemistry, University of Bristol, BS8 1TS, Bristol, UK   Email:   Email:
› Author Affiliations
Financial support from the Royal Thai Government, University of Bristol and EPSRC (EP/N024117/1) is acknowledged.
Further Information

Publication History

Received: 06 April 2018

Accepted after revision: 18 May 2018

Publication Date:
29 June 2018 (online)


The high regioselectivity associated with the iridium-catalysed borylation of pyridones has been exploited to provide a very direct and efficient entry to C(10) doubly substituted CC4 variants of cytisine. Two approaches have been evaluated based on (i) C–H activation of cytisine (or an N-substituted derivative) followed by N-alkylation (to enable dimer formation) and (ii) direct C–H activation and borylation of CC4 itself. Both approaches provide access to C(10)-functionalized CC4 derivatives, but direct borylation of CC4 allows for a wider range of functional group interconversions to be tolerated.

Supporting Information

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