BASE HYDROLYSIS OF COORDINATED THIOPHENE - A ROUTE FROM THIOPHENES TO FURANS AND THE PREPARATION OF [(C5ME5)RHS]4

The tetramethylthiophene (TMT) complex [Cp˙Rh(TMT)]2+ (Cp• = C5Me5) undergoes hydrolytic cleavage of the C-S bond upon treatment with aqueous KOH. The product has the formula Cp*Rh(MeCOC3Me3S). A single-crystal X-ray diffraction study, as well as spectroscopic methods, showed that the compound contains Cp˙Rh bound to an η4-acetylpropenethlolate group. HOSO2CF3 reverses the hydrolysis. Thermolysis of the ring-opened complex gives tetramethylfuran together with the cubane cluster [Cp*RhS]4. The hydrolysis reaction was shown to apply to [Ru(TMT)2](OTf)2 and [Ru(2,5-Me2H2C4S)(cymene)](OTf)2, which also gave acetylpropenethiolate complexes. © 1990, American Chemical Society. All rights reserved.