Dimeric Manganese-Catalyzed Direct Nucleophilic Addition of C(sp 2 )-H Bonds to Inert Aldehydes.

An efficient direct nucleophilic addition reaction of C(sp 2 )-H bonds to aldehydes catalyzed by a dimeric manganese has been developed. This reaction has a broad range of substrates, and high yields were also obtained with inert aliphatic aldehydes as substrates. A dimeric Mn 2 (CO) 8 Br 2 was proven to be a more efficient catalyst precursor than the monomeric Mn(CO) 5 Br.