Catalytic and Atom-Economic Cs-p3-C-sp3 Bond Formation: AlkylTantalum Ureates for Hydroaminoalkylation

摘要

Atom-economic and regioselective Csp3-Csp3 bond formation has been achieved by rapid C-H alkylation of unprotected secondary arylamines with unactivated alkenes. The combination of Ta(CH2SiMe3)(3)Cl-2, and a ureate N,O-chelating-ligand salt gives catalytic systems prepared insitu that can realize high yields of -alkylated aniline derivatives from either terminal or internal alkene substrates. These new catalyst systems realize C-H alkylation in as little as one hour and for the first time a 1:1 stoichiometry of alkene and amine substrates results in high yielding syntheses of isolated amine products by simple filtration and concentration.