Hydromagnesiation catalytic

Hydromagnesiation is not limited to carbon-carbon multiple bonds as discussed above, but also occurs with carbon-heteroatom unsaturated bonds as shown in Scheme 3.15. The hydromagnesiation of a earbon-oxygen double bond can be seen in reduction of ketones to secondary alcohols 111)41, esters to primary alcohols 11051. and carboxylic acids to aldehydes 1106] with i-BuMgBr in the presence of a catalytic amount... 

The accepted mechanism of the aforementioned liydromagnesiation of acetylenes in the presence of CpiTiCh can be drawn as in Scheme 3.12, which resembles that for hydromagnesiation of oletins in the presence of TiCLt (see Scheme 3.5 where the catalytically active species is CljTiH 5 ). 

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