RESUMO
The catalysed reaction of an enantiopure substrate with formation of a new chirality element may result in higher diastereoselectivity with one enantiomer of a catalyst (matched pair) than with the other (mismatched pair). The hypothesis that the matched reaction is faster was investigated using literature examples of kinetic resolution procedures that result in the formation of a new stereogenic centre. With one exception from fifteen examples, the selectivity factor (s = kfast/kslow) = kmatched/kmismatched. A model to estimate the relative rate of a fast-matched reaction vs. the corresponding slow-mismatched reaction is proposed. This model also provides insight into the basis of the selectivity displayed in the kinetic resolution procedures studied.
RESUMO
Retraction of 'Synthesis of a chiral dinuclear Cu(II)-benzothiazolamine complex: evidence of cuprophilic interaction in its structure and exploration of its electrochemical properties and catalytic performance' by O. Stephen Ojo et al., Dalton Trans., 2024, https://doi.org/10.1039/d3dt02994h.
RESUMO
The synthesis of dehaloperophoramidine, a non-halogenated derivative of the marine natural product perophoramidine, and its biological activity towards HCT116, HT29 and LoVo colorectal carcinoma cells is reported. A [3,3]-Claisen rearrangement and an epoxide opening/allylsilylation reaction installed the contiguous all-carbon quaternary stereocentres with the required relative stereochemistry.