N,N-diethyl O-carbamate: directed metalation group and orthogonal Suzuki-Miyaura cross-coupling partner.
The first Suzuki-Miyaura cross-coupling of an aryl O-carbamate, a versatile and powerful directed metalation group (DMG) in directed ortho metalation (DoM) chemistry, is described using the inexpensive, bench-stable catalyst NiCl(2)(PCy(3))(2). Broad synthetic scope and good efficiency are demonstrated for aryl and heteroaryl O-carbamates. The role of water and hydrolysis equilibrium between free boronic acid and boroxine was established to be a crucial parameter for this transformation. When combined with DoM and traditional Pd-catalyzed Suzuki-Miyaura strategies, the methodology offers concise routes to uniquely substituted molecules, avoiding the need for protection/deprotection of the phenol and the use of strongly nucleophilic cross-coupling partners.
Antoft-Finch
Aurora
A
Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada.
Blackburn
Tom
T
Snieckus
Victor
V
D002219:Carbamates / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
D002219:Carbamates; C547604:N,N-diethyl O-carbamate