Silyloxyphosphanes. New Phosphitylating Reagents in Nucleotide Chemistry

Abstract

Abstract Letsinger et al. developed a phosphite method of synthesis of oligonucleotides. This method was further improved by Carruthers et al. Our present work is a useful extension of the Letsinger-Carruthers type reagents. Recently, we have been able to demonstrate that bis- (N, N-diisopropylamino)trimethylsilyloxy phosphane exhibit phosphitylating properties in the presence 1-H-tetrazole.1 Preparation of this reagent and its ability to undergo selective nucleophilic substitution at the tricoordinate phosphorus atom without affecting the silicon center under conditions which are commonly used for the phosphite triester approach has been recently described.1 In the same paper we reported remarkable chemical properties of dinucleosidetrimethyl-siloxyphosphanes. Namely their participation in Michaelis-Arbuzov type reactions under extremely mild conditions and reactions with oxalylazolides and sulfuryl chloride fluoride which are unique for these reagents.