THE MOLECULAR AND CRYSTAL-STRUCTURE OF STABLE 5-METHYL-2-METHYLSULFONYL-3-THIOPHENECARBONITRILE OXIDE

A stable thiophene derivative, 5-methyl-2-methylsulfonyl-3-thiopheneca rbonitrile oxide, which is active in reactions with dipolarophiles, wa s studied by means of X-ray structural analysis. In the crystalline st ate the structure includes two independent molecules with similar valu es of geometric and conformation parameters. The bond angle at the C a tom of the nitrile oxide group is significantly different from 180-deg rees. The intramolecular distances between the C and S atoms in the ni trile oxide and sulfonyl groups are well below the equilibrium distanc e. The stability of the molecule is thought to be increased by electro static or donor-acceptor interactions between the atoms of these group s. The mutual orientation of the two independent molecules in the crys tal is nearly orthogonal.