Metal alkoxides reactions with unsaturated substrates

Metal alkoxides undergo insertion reactions across the M—O bonds (6) when treated with unsaturated substrates such as isocyanates, isothiocyanates, aldehydes, ketones, ketenes as well as with carbon dioxide, carbon disulfide, and sulfur dioxide. 

In addition to the general procedure iUusIrated by Eq. (2.182), another route has been employed for the synthesis of metal alkoxides (and particularly analogous siloxides) by the reaction of metal alkoxides with esters (and silyl esters) (Section 4.3). Further, the reactions of metal alkoxides with acyl halides (or hydrogen halides) and unsaturated substrates such as CO, CO2, CS2, organic-isocyanates and isothiocyanates, chloral, etc. have been utilized for the preparation of haUde-alkoxides (Section 4.11) and interesting insertion products (Section 4.12), respectively. 

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