Nitryl chloride, reaction with alkenes

With excess nitrosyl chloride, a chloronitro product is obtained in certain cases, a wide variety of ste-roid-5-enes giving 5a-chloro-6p-nitro derivatives in good yield (CH2CI2/CG4, to 0 C, 2-24 h). Nitryl chloride adds to terminal alkenes (56-80%) and to aoylic acid derivatives (refs. 239,240 and references cited therein) at temperatures close to amlrient. The reaction iq>peais to be a radical one, the NO2 entering the terminal position whatever the electronic requirement of the alkene. 

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