Structural investigations of ylides. Part II. Crystal and molecular structure of (+)-3-diazocamphor

Abstract

The title compound crystallises in the monoclinic system, space group P2₁, with Z= 2 in a unit cell of dimensions a= 7·119(2), b= 7·466(2), c= 9·279(2)Å, β= 91·75(2)°. The structure was solved from X-ray diffractometer data by comparison with the structures of certain other isomorphous (+)-camphor derivatives, and was refined by least-squares techniques to R 0·087 for 661 independent reflexions. The results of the analysis indicate that stabilisation of diazoketones via the diazo-function occurs to an extent similar to that which would be expected for the less stable diazoalkanes, with the additional stability resulting from small contributions from the enolate forms of diazoketones.