Concentration effects in chelation controlled reactions

Article abstract of DOI:10.1016/0040-4039(95)01897-Q

The diastereoselectivities of addition reactions of allyltrimethylsilane to an α-benzyloxyaldehyde were found to be relatively insensitive to the amount of added TiCl₄, and to the absolute concentration of the 1:1 aldehyde/TiCl₄ complex. In contrast, diastereoselectivities of similar additions to a structurally related β-benzyloxyaldehyde were highly dependent on these variables.