Weak force in action: In the title reaction, the palladium catalyst (see figure, left) uses weak CH⋅⋅⋅O hydrogen bonding to control the absolute configuration of the new stereocenter. A similar palladium catalyst (right) used conventional NH⋅⋅⋅O hydrogen bonding to guide stereoselection.
Regioselective Hydroformylation of Allylic Alcohols
作者:Thomas E. Lightburn、Omar A. De Paolis、Ka H. Cheng、Kian L. Tan
DOI:10.1021/ol200782d
日期:2011.5.20
hydroformylation of allylicalcohols is reported toward the synthesis of β-hydroxy-acid and aldehyde products. The selectivity is achieved through the use of a ligand that reversibly binds to alcohols in situ, allowing for a directed hydroformylation to occur. The application to trisubstituted olefins was also demonstrated, which yields a single diastereomer product consistent with a stereospecific addition of CO
据报道,烯丙醇的高度区域选择性加氢甲酰化可用于合成 β-羟基酸和醛产物。选择性是通过使用一种配体来实现的,该配体在原位可逆地结合醇,允许发生定向加氢甲酰化。还证明了三取代烯烃的应用,这产生了与 CO 和氢的立体有择加成一致的单一非对映异构体产品。