Regio- and Enantioselective Linear Cross-Dimerizations between Conjugated Dienes and Acrylates Catalyzed by New Ru(0) Complexes
journal contributionposted on 2014-11-24, 00:00 authored by Yuki Hiroi, Nobuyuki Komine, Sanshiro Komiya, Masafumi Hirano
New naphthalene complexes of Ru(0) with various Ru(η6-naphthalene)(cyclic diene) (3) ligands catalyze linear cross-dimerization between conjugated dienes and acrylates. One of the noteworthy catalysts is the dibenzocyclooctatetraene complex 3d, which shows high catalytic activity for the cross-dimerization between 1,3-pentadiene and methyl acrylate to give the cross-dimers in 99% yield (branch/linear = 77/23) within 1 h at 50 °C with 1 mol % catalyst loading. When Ru(η6-naphthalene)[(−)-Ph-bod*] (3f) was used as the catalyst, treatment of 2,4-dimethylhexa-2,4-diene with tert-butyl acrylate produced the chiral cross-dimer in 44% yield with 49% ee. This is the first example of enantioselective cross-dimerization between conjugated dienes and substituted alkenes.