Hydrosilylation of Diene Derivatives Catalyzed by Fe-Iminobipyridine Complexes Aiming at Syntheses of Organosilane Compounds Containing a Terminal Olefin Portion

• Published in: Bulletin of the Chemical Society of Japan Vol. 92; no. 1; pp. 105 - 114
• Main Authors: Kobayashi, Katsuaki, Teratani, Sayaka, Izumori, Yosuke, Hayasaka, Kazumasa, Nakazawa, Hiroshi
• Format: Journal Article
• Language: English
• Published: TOKYO The Chemical Society of Japan 01.01.2019; Chemical Soc Japan; Chemical Society of Japan
• Subjects: Butadiene; Catalysis; Chemistry; Chemistry, Multidisciplinary; Hydrosilylation; Ligands; Physical Sciences; Science & Technology; Selectivity; Steric effects; Steric hindrance; Hydrosilylation of diene; Hydrosilylation catalyst; Fe complex; INORGANIC HYBRID GELS; CYCLIZATION/HYDROSILYLATION; IRON CATALYSTS; SILANE COUPLING AGENTS; DEHYDROGENATIVE SILYLATION; HOMOGENEOUS CATALYSIS; SYSTEMS; STEREOSELECTIVE HYDROSILYLATION; ALKENE HYDROSILYLATION; COBALT
• ISSN: 0009-2673; 1348-0634
• DOI: 10.1246/bcsj.20180197

The catalytic ability of Fe-iminobipyridine complexes ((BPI)FeBr2, BPI = iminobipyridine) for hydrosilylation of both a non-conjugated diene and a conjugated diene was investigated aiming at the production of organosilane compounds bearing a terminal olefin portion. Steric effects of (BPI)FeBr2 were controlled by the substituents at the terminal pyridine ring (R1), the imino carbon (R2), and the imino nitrogen (Ar) of the BPI ligand. As regards a non-conjugated diene, hydrosilylation of 1,7-octadiene with diphenylsilane (Ph2SiH2) produced a mixture of mono- and di-hydrosilylated compounds. To obtain the mono-hydrosilylated compound preferably in the 1:1 reaction of non-conjugated diene and silane, the substituent effect of the BPI ligand was investigated. As a result, larger steric hindrance of (BPI)FeBr2 based on substituents slowed the hydrosilylation, instead the selectivity of the mono-hydrosilylated compound was substantially improved. The 6′-Me group on a terminal pyridine was most effective. Finally, production of the mono-hydrosilylated compound from 1,7-octadiene and Ph2SiH2 reached 77% yield and 0.94 selectivity. In the case of a conjugated diene, (BPI)FeBr2 with any substituents selectively generated 1,4-hydrosilylated compound in hydrosilylation of 2,3-dimethyl-1,3-butadiene with Ph2SiH2. In this case, higher steric hindrance of (BPI)FeBr2 simply decreased the yield of the product.