Solvent and salt effects on the reactions of allyltin (IV) compounds with singlet oxygen, 4-phenyl-1,2,4-triazoline-3,5-dione and diethyl azodicarboxylate

The effect of the increase of polarity of the solvent binary mixture methanol–benzene on the selectivity and the rate of metalloene reactions of different allyltin compounds with singlet oxygen, 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) and diethyl azodicarboxylate (DEAD) was studied. Analogous comparative studies were carried out in Et2O and 4 mol dm−3 solutions of LiClO4 in diethyl ether. In the reaction with PTAD and 1O2 the more polar solvent favoured the production of the M-ene product, whereas the cycloaddition reaction was favoured by a non-polar solvent.