2 Chlorophenyl phosphorodichloridothioate, synthesis

CHLOROPHENYL PHOSPHORODICHLORIDOTHIOATE as a coupling agent. A convenient synthesis of multigram quantities of VITAMIN D2 FROM ERGOSTEROL is detailed, and the syntheses of 5,15-DIPHEN-YLPORPHYRIN, and 9,10-DIPHENYLPHENANTHRENE constitute the final two procedures in this volume. 

Phase transfer catalysis4 is a valuable tool in organic synthesis. The process is exemplified by the convenient synthesis of 2-chlorophenyl phosphoro-dichloridothioate. Using this phase transfer reaction, a number of dichloridothioates of substituted phenyl, benzyl, thiophenyl, and thiobenzyl alcohols are accessible. The phosphorodichloridothioate reacts with various coupling reagents to form activated species that are useful in the synthesis of oligonucleotide phosphorothioates via the phosphotriester approach as illustrated below.5 6... 

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