Chemistry Department, Loughborough University, Loughborough, Leics. LE11 3TU, UK.
Org Biomol Chem. 2013 Sep 21;11(35):5926-35. doi: 10.1039/c3ob40884a.
Ketones are prepared from aldehydes via 1-benzyl-2-(1-hydroxyalkyl)-4,5-dihydroimidazoles (adducts of the aldehydes with 1-benzyl-2-lithio-4,5-dihydroimidazoles) whereas 1-benzyl-2-(1-oxoalkyl)-4,5-dihydroimidazoles are shown to act as acyl transfer reagents via C-C bond cleavage. 4,5-Dihydroimidazolium ylides (NHCs) are intermediates in both processes, which constitute thiamine-inspired C-C bond formation and cleavage protocols.
酮可以通过 1-苄基-2-(1-羟烷基)-4,5-二氢咪唑（醛与 1-苄基-2-锂-4,5-二氢咪唑的加成物）制备，而 1-苄基-2-(1-氧代烷基)-4,5-二氢咪唑则通过 C-C 键断裂作为酰基转移试剂。4,5-二氢咪唑𬭩盐（NHCs）是这两种过程的中间体，它们构成了受硫胺素启发的 C-C 键形成和断裂的方案。
