Phosgene, reaction with oximes

The reaction of 2-amino-5-chlorobenzophenone oxime (8) with phosgene affords the benzoxa-diazcpinone 9.316... 

On the other hand, vV-aryl-//-nitrosoaminonitriles undergo interesting secondary reactions. Under acidic conditions, salts of the sydnonimes form (Eq. 13) under basic conditions, a rearrangement to an isomeric oxime takes place, which, on treatment with phosgene in pyridine leads to 4-substituted-3-cyano-l,2,4-oxadiazolinones (Eq. 14) [26b],... 

Oxo-l,2,4-oxadiazepines (507) have been prepared by the reaction of hydroxyurea with some a, (3-unsaturated ketones (75TL2979). sy -to-(Benzylamino)propiophenone oximes (508) react with phosgene to give the 7-oxo-l,2,6-oxadiazepines (509) (75CB3387), and with formaldehyde to give (510) (80CB3373). 

The diazepine 85 (tetramethyleneurea) has been prepared by a variety of routes. Among these are the treatment of tetramethylene diisocyanate with water,70-72 the rearrangement of the oxime (86) in polyphosphoric acid,73,74 and the reaction of 1,4-diaminobutane with sulfur, methanol, and carbon monoxide at high pressure.75 A novel preparation of 85 involves the reaction of 1,4-diaminobutane with 87 to give the silylated diamine (88). Reaction of 88 with phosgene and triethylamine yielded the bistrimethylsilyldiazepine (89) which was then hydrolyzed in aqueous ethanol to give 85.76... 

Reaction of phosgene with the anti isomer of 1-amino-1-phenyl-2-propanone oxime gives l-hydroxy-5-methyl-4-phcny -3-iraidazolin-2-one in 25% yield [49]. A review of A -oxide formation has appeared recently [50], and discussions of other approaches to the compounds are found in Section 4.1 and Chapter 5. 

The reaction of a r/-a-amino-oximes with phosgene gives 2-oxo-3-imida-zoline-3-oxides (344), whose structure was demonstrated by 1,3-dipolar additions, giving (345), and by spectroscopic methods. The 4,5,5-trimethyl... 

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