Hydroformylation and related reactions of vinylsilanes catalyzed by siloxide complexes of rhodium(I) and iridium(I)

• Published in: Journal of molecular catalysis. A, Chemical Chemical, 2005-08, Vol.237 (1), p.246-253
• Main Authors: Mieczyńska, Ewa, Trzeciak, Anna M., Ziółkowski, Józef J., Kownacki, Ireneusz, Marciniec, Bogdan
• Format: Article
• Language: English
• Subjects: 1-Siloxypropene; Catalysis; Chemistry; Exact sciences and technology; General and physical chemistry; Hydroformylation; Iridium(I)-siloxide complexes; Isomerization; Rhodium(I)-siloxide complexes; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Vinylsilanes
• ISSN: 1381-1169; 1873-314X
• DOI: 10.1016/j.molcata.2005.04.054

Rhodium(I) and iridium(I) siloxide complexes used as catalysts of hydroformylation of the vinylsilanes at 80 °C and 10 atm of H 2/CO (H 2:CO = 1) produced aldehydes ( n + iso) as the main products with yields of up to 100%. In the presence of the iridium complexes some amounts of ethylsilanes, up to 40%, were obtained, besides aldehydes, as a result of hydrogenation of the substrates. In the presence of the rhodium complexes, isomerization of iso-aldehydes to 1-siloxypropenes was observed under the reaction conditions. Under 10 atm of H 2, the rhodium complexes appeared to be also very effective catalysts of vinylsilanes hydrogenation. ▪ Rhodium(I) and iridium(I) complexes of the formula [(cod)Rh(OSiMe 3)(PPh 3)] (1), [(cod)Rh(OSiMe 3)(PCy 3)] (2), [(cod)Rh(OSiMe 3)] 2 (3), [(cod)Ir(OSiMe 3)(PCy 3)] (4), and [(cod)Ir(OSiMe 3)] 2 (5), used as catalysts of hydroformylation of the vinylsilanes Me 3SiCH CH 2, Me 2PhSiCH CH 2, (MeO) 3SiCH CH 2, and Me 2PhSiCH CHPh at 80 °C and 10 atm of H 2/CO (H 2:CO = 1), produced aldehydes ( n + iso) as the main products with yields of up to 100%. In the presence of the iridium complexes (4) and (5), some amounts of ethylsilanes, up to 40%, were obtained, besides aldehydes as a result of hydrogenation of the substrates. In the presence of the rhodium complexes (1) and (2), isomerization of iso-aldehydes to 1-siloxypropenes was observed under the reaction conditions. Under 10 atm of H 2, the rhodium complexes appeared to be very effective catalysts of vinylsilanes hydrogenation. The hydrogenation reaction products, in addition to ethylsilanes, also included products of homocoupling of vinylsilanes (hydrogenated and non-hydrogenated).