Aryl phosphorodichloridates, synthesis

Aryl phosphorodichloridates, synthesis of spirobis[l,3,2-benzoxaza-phosphole], 163... 

Polynucleotides. Aryl phosphorodichloridates (1,847) are useful for synthesis of short oligonucleotides by the phosphotriester procedure however, the reactions are slow and yields are low as the chain length is increased. However, aryl phosphorodichloridites react with hydroxyl groups in THF at -78°... 

A versatile synthesis of 6a -thia-l,2,6-triazapentalenes and 6a -thia-6-selena-l,2-diazapentalenes has been reported from oxathiadiazapentalene (542) <83JCS(P1)777>. Treatment of (542) with phos-phoryl chloride in 1,2-dichloroethane gave the 5-(2-chlorovinyl)-2-phenyl-l,2,3-thiadiazolium phos-phorodichloridate (543) which, when treated with perchloric acid in acetic acid, afforded the stable crystalline perchlorate (544) in nearly quantitative yield. The phosphorodichloridate (543) reacted with aliphatic and aryl amines to give the thiatriazapentalenes (545) in acceptable yields (44-97%) (Scheme 46). 

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