Palladium-Catalyzed Alkoxycarbonylation of Unactivated Secondary Alkyl Bromides at Low Pressure.
Catalytic carbonylations of organohalides are important C-C bond formations in chemical synthesis. Carbonylations of unactivated alkyl halides remain a challenge and currently require the use of alkyl iodides under harsh conditions and high pressures of CO. Herein we report a palladium-catalyzed alkoxycarbonylation of secondary alkyl bromides that proceeds at low pressure (2 atm CO) under mild conditions. Preliminary mechanistic studies are consistent with a hybrid organometallic-radical process. These reactions efficiently deliver esters from unactivated alkyl bromides across a diverse range of substrates and represent the first catalytic carbonylations of alkyl bromides with carbon monoxide.
Department of Chemistry, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
Brendon T
BT
Sargent
Department of Chemistry, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
Erik J
EJ
Alexanian
D000438:Alcohols / Q000737:chemistry; D000473:Alkanes / Q000737:chemistry*; D002384:Catalysis; D006842:Hydrocarbons, Brominated / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry*; D011312:Pressure
D000438:Alcohols; D000473:Alkanes; D006842:Hydrocarbons, Brominated; D009942:Organometallic Compounds; C059688:alkoxyl radical; D010165:Palladium