Chloronitrile oxide

Pasinszki and Westwood investigated the dimerization of chloronitrile oxide CICNO to 3,4-dichloro-l,2,5-oxadiazole-2-oxide 78 (Scheme 48) [98JPC(A) 4939]. From B3-LYP/6-31G calculations, they conclude that the reaction path can be characterized as a typical Firestone-type cycloaddition, a two-step mechanism with a C—C bond forming characterizing the first reaction step. The activation... 

We entered this field when we studied the photoisomerization of simply substituted nitrile oxides 138 (R = Cl, Br, CN).188 Matrix irradiation yields the corresponding isocyanates 144. In the case of chloronitrile oxide besides the absorptions of chloroisocyanate189 the bands of chloronitrene190 also appear. It can be assumed that the nitrile oxide-isocyanate rearrangement starts with the ring closure 138 - 140.191192... 

The addition of nitrile oxides to 1,3-dipolar intermediates is a well established route to isoxazolines. Chloronitrile oxide (295) has been added to the nitronate salts of ttjS-unsaturated a-nitro crotonic esters (296) to yield the 3-chloroisoxazoline adducts (297) which are useful substrates for transformation into biologically interesting amino acids. ... 

The action of aqueous potassium hydroxide on chloronitrile 14 in DMSO at 25-30°C accomplishes the hydrolysis of the chloronitrile moiety and furnishes ketone 13 in a yield of 80%. Treatment of a solution of ketone 13 in CH2CI2 with mCPBA and sodium bicarbonate results in a selective Baeyer-Villiger oxidation to give bicyclic lactone 12 in >95% yield. It is noteworthy that the Baeyer-Villiger oxidation is completely regioselective and that the... 

Pyrazolo[3,4-. ]pyridines have also been formed by reaction of the appropriate chloronitrile pyridine (Equation 50) <2002BML2925>. Pyrazolo[3,4-. ]pyridines can be prepared by oxidative cyclization with PIFA (Equation 51 Table 27) <1997SC2217>. 

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