Mild and practical method for the silylation of alcohols using hydrosilanes and disilanes promoted by TBAF catalyst
摘要:
The primary and secondary alcohols were conveniently silylated (t-BuMe(2)Si-, Et(3)Si-, and Me(2)PhSi-) using the hydrosilanes, and sterically hindered alcohols were also silylated (Me(3)Si- and MePh(2)Si-) using the disilanes, promoted by tetrabutylammonium fluoride (TBAF) catalyst under mild conditions.
A fluorine-containing vitamin D.sub.2 derivative represented by the following formula ##STR1## wherein R.sup.1 represents a methyl or trifluoromethyl group, and R.sup.2 represents a trifluoromethyl group when R.sup.1 is a methyl group, and a hydrogen atom or a methyl group when R.sup.1 is a trifluoromethyl group. This compound is useful for the prevention or treatment of calcium pathobolism or osteoporosis.
Large-scale preparation and labelling reactions of deuterated silanes
作者:Jesús Campos、Miguel Rubio、Ana C. Esqueda、Ernesto Carmona
DOI:10.1002/jlcr.1950
日期:2012.1
A catalytic synthesis of deuterated silanes SiEt3D, SiMe2PhD and SiPh2D2 is reported that allows their facile generation in a 3–4 g scale, utilizing D2 (0.5 bar) as the hydrogen isotope source and low catalyst loadings (0.01 mol%). The catalyst precursor is the rhodium (III) complex 1, which contains a (η5-C5Me5)Rh cation stabilized by coordination to a cyclometallated phoshine PMeXyl2 (Xyl = 2,6-C6H3Me2)