Isocyanatophosphoric Acid Dichloride: A Novel Reagent for the Introduction of a Cyano Group into the Molecules of Electron-Rich Heterocycles and Enamines­

Abstract

A new synthetic method is developed which enables a direct one-step introduction of a cyano group into electron-rich heterocyclic systems of the indole, pyrrole, and indolizine series, and also to enamines using isocyanatophosphoryl dichloride.

N-Acylamidophosphinates: Structure, Properties and Complexation Towards Main Group Metal Cations

“…The products 12 and 13 were isolated in high yields (70-99%). They are of interest due to the presence of biologically active Het-moieties and were used as intermediates for heterocycles with carbamoyl-14 and cyano-substituents 15 (Scheme 9) [21][22][23][24].…”

Isocyanatophosphoryl Dichloride as Reagent for Introduction of Carbamoyl Group into Molecules of π-Excessive Heterocycles and Enamines

“…isocyanatophosphoryl dichloride, which was efficiently employed by us earlier to introduce a diaminophosphorylcarbamoyl as well as a cyano group into the molecules of p-excessive heterocycles and enamines. 6,7 In the present paper we report the application of isocyanatophosphoryl dichloride for converting a number of pexcessive heterocycles and enamines into primary amides of hetarene-and cycloalkenecarboxylic acids. The method developed involves hydrolytic cleavage of the initially forming products 2 from isocyanate addition (see Scheme 1).…”

“…This is evidently due to the tendency of acids 3 and their derivatives to thermally decompose to nitriles. 6,9 A minor impurity consisting of readily soluble nitriles in target carboxamides 4 is easily removed by recrystallization.…”

Intramolecular Cyclization of N‐Arylphosphinimidic Isocyanates – Novel Approach to a 4a,8a‐Dihydro‐1,3,2λ5‐benzodiazaphosphinin‐4(3H)‐one System

“…It could be assumed that the conversion, similar to the one presented in Scheme 1, would be possible when the carbon atom adjacent to the isocyanate group is replaced by a phosphorus atom (see Scheme 2), since electron-donating properties of the phosphinimine fragment and C-carbamoylating properties of phosphorus isocyanates are well known. [7][8][9][10] The route proposed leads to a previously unavailable type of 1,3,2λ 5 -benzodiazaphosphinin-4(3H)-one 5 containing an endocyclic P=N double bond (for the synthesis of the closest topological analogues see refs. [11][12][13] ).…”