Catalytic and Atom-Economic Csp3 -Csp3 Bond Formation: Alkyl Tantalum Ureates for Hydroaminoalkylation.

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(CH2 SiMe3 )3 Cl2 , and a ureate N,O-chelating-ligand salt gives catalytic systems prepared in situ that can realize high yields of β-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.