Pyrroles 1,3-oxazepines

A 1,3-oxazepine derivative (158) has been isolated in low (2-3%) or unspecified yield by treatment of the Z-ketovinylazirine 157 with diiron nonacarbonyl50 or molybdenum hexacarbonyl,51 respectively (Scheme 182) the major products of these reactions are pyrrole derivatives (see Scheme 23 in Section IV,A,1). There is no preparative value in this type of oxazepine synthesis (Scheme 182) since the transformation can be affected efficiently in a thermal reaction at 100°C.52... 

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