Cyclopropylmethoxycarbenium complexes

A different strategy is utilized to prepare Fischer-type cyclopropylmethoxycarbenium complexes. [LM C=(OMe)(c-Pr)]+ by alkylation of cyclopropylcarbonyl complexes c-PrC(0)ML (vide supra). Thus, treating acyl complex FpCO(c-Pr), obtained from the reaction of NaFp [Fp = Cp(CO)2] and c-PrCOCI, with Me,0+BF4 in CH2C12 gives cyclopropylmethoxycarbenium fluoroborate complex salt [Fp=C(OMe)(c-Pr)]BF4 (equation 68) which can be further reduced to the corresponding Schrock-type cyclopropyl carbene complex (vide infra, Section II.C.2)142. 

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