Functionalised organotitanium compounds: from lithium to titanium intermediates in chemoselective reactions with carbonyl compounds

The reaction of functionalised organolithium compounds 1 with an equimolecular mixture of two carbonyl compounds in the presence of 2 equiv. of triisopropoxytitanium chloride can discriminate between aldehyde and ketone, the process being selective for aldehydes at room temperature. Electronic and steric effects have been observed for different aldehydes.