Boron trifluoride thietane

The block copolymer of ethylene oxide and 3,3-dimethylthietane shows useful properties of complexing halogen and heavy metal salts (79MI51402). Thietanes can be polymerized with methylmagnesium iodide as well as with a variety of electrophiles such as methyl sulfate, trimethyloxonium tetrafluoroborate, triethylaluminum, boron trifluoride and phosphorus trifluoride (67IC1461, 67MI51400). Thietane (210) has been patented as a stabilizer for poly(vinyl chloride) (73USP3767615). 

Other Lewis acids that complex with thietane are titanium tetrachloride or bromide,boron trifluoride,trimethylaluminum, and tin tetrachloride. The enthalpies of formation of the aluminum complex (— 16.04 kcal/mole) and the tin complex (— 14.2 kcal/mole) and the wavelength of the charge transfer band of the tin complex (270 nm) have been determined. The titanium tetrahalides form both a 1 1 and a 1 2 adduct (titanium halide thietane). °° Treatment of 3-methyl-thietane with aluminum chloride or tin tetrachloride yields a rubbery white soUd." "... 

The reaction of bisthiomalonic acids R R C(COSH)a with isopropenyl acetate, acetone, and other carbonyl compounds in the presence of boron trifluoride etherate yields thietan-2,4-diones. 2,2,4,4-Tetramethylcyclobutane-l,3-dithione reacts with methylenetriphenylphosphorane to yield a 2-thioxo-thietan (38 X = S). The monothiodiketone yields a 2-keto-thietan (38 X = O). 

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