Thermal telomerization of olefins with silanes

Advances in Base-Metal-Catalyzed Alkene Hydrosilylation

“…The first example of Fe-catalyzed alkene hydrosilylation was reported by Nesmeyanov and co-workers in 1960 using Fe­(CO) 5 as the catalyst precursor (Scheme ). , Mechanistic studies by Graham and Wrighton revealed that the dissociation of the CO ligand(s) was required to generate the catalytically active [Fe­(CO) 4 ] or [Fe­(CO) 3 ] species. , The catalyst activation required continuous photoirradiation or thermolysis at high temperatures (100–140 °C). The hydrosilylation reactions of α-olefins occurred with 1.5–3 mol % of Fe­(CO) 5 to form the anti -Markovnikov hydrosilylation products in moderate to good yields.…”

“…In comparison with the reactions catalyzed by its iron analogue, Fe­(CO) 5 (Scheme ), the hydrosilylation with Co 2 (CO) 8 proceeded under milder conditions (0–60 °C) and in a more selective manner (Scheme ). The side reactions, dehydrogenative silylation and hydrogenation that often occurred in the catalysis using Fe­(CO) 5 , were not observed in the Co-catalyzed process. , However, Co 2 (CO) 8 could effect the isomerization of 1-alkenes to form inactive internal alkenes, and thus, an excess of alkenes (3 equiv relative to silane) was required. Later, Kalinin and co-workers broadened the substrate scope of the Co 2 (CO) 8 -catalyzed hydrosilylation .…”