Categories: C-Si Bond Formation > Siloxanes
Synthesis of vinylsiloxanes
Grubbs' first-generation Ru metathesis complex catalyses the hydrosilylation of terminal alkynes. The reaction exhibits an interesting selectivity profile that is dependent on the reaction concentration and more importantly on the silane employed.
C. S. Arico, L. R. Cox, Org. Biomol. Chem., 2004, 2, 2558-2562.
Low catalyst loadings of (IPr)Pt(allyl ether) display enhanced activity and regioselectivity for the hydrosilylation of terminal and internal alkynes. Reactions lead to exquisite regioselectivity in favor of the cis-addition product on the less hindered terminus of terminal and internal alkynes.
G. Berthon-Gelloz, J.-M. Schumers, G. De Bo, I. E. Markó, J. Org. Chem., 2008, 73, 4190-4197.
A silyl-Heck reaction allows the preparation of vinyl silyl ethers and disiloxanes rom aryl-substituted alkenes and related substrates using a commercially available catalyst system and mild conditions. This work represents a highly practical means of accessing diverse classes of vinyl silyl ether substrates in an efficient and direct manner with complete regiomeric and geometric selectivity.
S. E. S. Martin, D. A. Watson, J. Am. Chem. Soc., 2013, 135, 13330-13333.
Ruthenium alkylidenes catalyze regio- and stereoselective dehydrogenative silylations and hydrosilylations of vinylarenes with alkoxysilanes. Depending on the ligand, the method offers selective access to either (E)-vinylsilanes or β-alkylsilanes with high regio- and stereocontrol.
A. Bokka, J. Jeon, Org. Lett., 2016, 18, 5324-5327.
A bench-stable alkyl bisphosphine Mn(I) complex catalyzes an additive-free Mn(I)-catalyzed dehydrogenative silylation of terminal alkenes. A broad variety of aromatic and aliphatic alkenes was efficiently and selectively converted into E-vinylsilanes and allylsilanes, respectively, at room temperature.
S. Weber, M. Glavic, B. Stöger, E. Pittenauer, M. Podewitz, L. F. Veiros, K. Kirchner, J. Am. Chem. Soc., 2021, 143, 17825-17832.
A well-defined low-valent cobalt(I) catalyst [HCo(PMe3)4] enables a highly regio- and stereoselective hydrosilylation of internal alkynes. The reaction provides in many cases a single hydrosilylation isomer for various hydrosilanes and unsymmetrical alkynes.
A. Rivera-Hernández, B. J. Fallon, S. Ventre, C. Simon, M.-H. Tremblay, G. Gontard, E. Derat, M. Amatore, C. Aubert, M. Petit, Org. Lett., 2016, 18, 4242-4245.
Palladium catalyzes a highly regio- and stereoselective hydrosilylation applicable to a broad range of electron-deficient alkynes. The resulting α-silylalkenes can be further transformated using particularly Hiyama coupling and stereoinverting iododesilylation followed by Suzuki-Miyaura coupling, which enables stereodivergent syntheses of α-arylenoates.
Y. Sumida, T. Kato, S. Yoshida, T. Hosoya, Org. Lett., 2012, 14, 1552-1555.
In the presence of Pd(0) and a phosphine, a hydrosilylation of 1,3-enynes with Me2SiHCl yields dienylsilanes with (E)-configuration and with the silicon group added to the internal alkyne carbon atom. Subsequent hydrolysis gives silanols, that serve as precursors to conjugated dienes with different substitution patterns.
H. Zhou, C. Moberg, Org. Lett., 2013, 15, 1444-1447.