Studies on a catalytic version of the Matteson asymmetric homologation reaction

Studies of a catalytic asymmetric version of the Matteson reaction between dichloromethylboronates and organolithium reagents have been undertaken. From several different chiral catalytic systems studied, only one based on a mannitol derivative has given substantial asymmetric induction close to that previously achieved with a bis(oxazoline) derivative and ytterbium triflate. More detailed study of the latter reaction revealed that fresh ytterbium triflate actually reduced the level of asymmetric induction, while aged ytterbium triflate, or a fresh sample that had been treated with water, brought about improved induction. The implications of these findings are discussed.

Automated summary

Studies have shown that a chiral catalytic system based on a mannitol derivative in the catalytic asymmetric version of the Matteson reaction provides substantial asymmetric induction similar to that achieved with a bis(oxazoline) derivative and ytterbium triflate. Additionally, it was found that fresh ytterbium triflate may reduce the level of asymmetric induction, while aged ytterbium triflate or a fresh sample treated with water can improve the induction effect.