DIISOPROPYLDICHLOROSILANE

bp 50–55°C/5 mmHg.

Dichlorodiisopropylsilane can be used in nucleoside 3',5'-hydroxy protection; component in Peterson alkenation reaction. The use of silicon groups as protection for hydroxy groups has been widely exploited.3 One potentially useful way to protect a nucleoside is by using a protecting group which spans the 3- and 5-hydroxy groups. One of the useful groups which can be used as a bifunctional protecting group in nucleosides is the diisopropylsilyl group. Reaction of the nucleoside with dichlorodiisopropylsilane and imidazole in DMF gives the protected nucleoside (eq 1).This method has not been widely used; the more common 3',5'-hydroxy-bridging protecting group is a tetraisopropyldisiloxy group.

conveniently prepared by the reaction of diisopropylsilane in carbon tetrachloride with palladium(II) chloride at 140°C for 8 h in a steel bomb.Washing the residue with ether and removing the ether by rotary evaporation yields the product which is purified by distillation to yield a clear colorless oil.