Summary Trichlorotitanium dialkylamino-alkoxides (2; titanates of N, O-hemiacetals) are generated either from the corresponding lithium alkoxides and titanium tetrachloride (Scheme I) or by addition of trichloro-dialkylamino-titanium to aldehydes. The electrophilic (dialky1amino) alkylating reagents 2 are used to convert lithium enolates to/3-dialkylamino- ketones and-esters 5 (Mannich bases), see Scheme 2 and Table. One diastereoisomer of ...