Olefin metathesis hydrogen transfer processes

Several studies now exist which add credence to Casey s attractive proposal that metallocyclobutanes intervene in metathesis and cyclopro-panation reactions. Additionally, metallocyclobutanes have been observed to interconvert to propylene derivatives by way of /3-hydrogen transfer reactions. It is not well established, however, whether precoordination of the reacting olefin is required in all these processes. The proposed interrelation of these reactions may be formally presented as follows ... 

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