Categories: C-Si Bond Formation >
Electrophilic Silylation
Reactions
Various siletanes have been used as substrates for the oxidation of
carbon-silicon bonds upon exposure to aqueous fluoride and peroxide. These
tetraalkylsilanes offer a combination of stability and reactivity with many
practical benefits, including compatibility with silicon protecting groups
and electron-rich aromatic rings.
J. D. Sunderhaus, H. Lam, G. B. Dudley, Org. Lett.,
2003, 8, 4571-4573.
By treatment with s-BuLi/TMEDA at -78°C, unprotected 2-methoxybenzoic
acid is deprotonated exclusively in the position ortho to the
carboxylate. A reversal of regioselectivity is observed when the acid is
treated with n-BuLi/t-BuOK.
T.-H. Nguyen, A.-S. Castanet, J. Mortier, Org. Lett.,
2006, 8, 765-768.
General reaction conditions for the synthesis of
aryl(trialkoxy)silanes from aryl Grignard and lithium reagents and tetraalkyl
orthosilicates (Si(OR)4) have been developed. Ortho-, meta-,
and
para-substituted bromoarenes underwent efficient metalation and
silylation at low temperature to provide aryl siloxanes.
A. S. Manoso, C. Ahn, A. Soheili, C. J. Handy, R. Correia, W. Seganish, P.
DeShong, J. Org. Chem.,
2004,
69, 8305-8314.
A. S. Manoso, C. Ahn, A. Soheili, C. J. Handy, R. Correia, W. Seganish, P.
DeShong, J. Org. Chem.,
2004,
69, 8305-8314.
A rapid and high-yielding silylation of terminal alkynes employing TMSOTf and
catalytic quantities of Zn(OTf)2 works well for a variety of substrates
including reactive esters.
R. J. Rahaim, Jr., J. T. Shaw, J. Org. Chem., 2008,
73, 2912-2915.
Various alkynylsilanes were efficiently prepared via zinc halides-mediated direct silylation of terminal alkynes with aminosilanes. Base- and nucleophile-sensitive functionalities were tolerated under the reaction conditions. The electrophilic character of this transformation is supported by initial mechanistic studies.
A. A. Andreev, V. V. Konshin, N. V. Komarov, M. Rubin, C. Brouwer, V. Gevorgyan, Org. Lett., 2004, 6, 421-424.
Hippadine and pratosine - members of the pyrrolophenanthridone alkaloid
family - were synthesized.
C. G. Hartung, A. Fecher, B. Chapell, V. Snieckus, Org. Lett.,
2003, 5, 1899-1902.
