CARBENOID REACTIONS OF TRIFLUOROMETHYLELEMENT COMPOUNDS .2. THE REACTIONS OF BIS(TRIFLUOROMETHYL) CADMIUM COMPLEXES WITH CYCLIC ETHERS AND THIOETHERS - A CD-113 NMR AND F-19 NMR-STUDY OF THE INTERMEDIATES

The reactions of Cd(CF3)(2) . 2CH(3)CN with tetrahydrofuran (THF), tet rahydrothiophene and tetrahydrothiopyran in the presence of BF3 . CH3C N yield open-chain difluoromethyl ethers and thioethers. The final pro duct from the reaction with tetrahydrothiophene, [4-(difluoromethylthi o)butyl] tetrahydrothiophenium tetrafluoroborate, has been fully chara cterized, whereas the products of the reactions with THF yielded polym eric ethers containing the OCF2H group. All cadmium-containing interme diates formed during the reaction with tetrahydrothiophene could be de tected by Cd-113 and F-19 MMR spectroscopy indicating that a carbenoid mechanism is more likely than a 'free' difluorocarbene mechanism. In contrast to the reactions of the trifluoromethylcadmium derivative wit h THF in the presence of BF3, reactions in the presence of BCl3 or InC l3 yielded 4-chlorobutyl(difluoromethyl) ether.