Cycloadditions of 1,3-oxazolium-4-olates (isomünchnones) by rhodium(II)-induced decomposition of α-diazocarbonyl derivatives of (5R)- and (5S)-phenyloxazin-3-one as a chiral template
作者:Richard Angell、Marion Fengler-Veith、Harry Finch、Laurence M. Harwood、Toby T. Tucker
DOI:10.1016/s0040-4039(97)00918-0
日期:1997.6
Cycloadducts (6–9) were synthesised from isomünchnone derivatives of (5R)- and (5S)-phenyloxazin-3-one by rhodium(II)-catalysed decomposition of α-diazocompounds (3a-c). Additions to various carbon-carbon dipolarophiles proceeded with high and moderate diastereofacial selectivities.
Cycloadditions of chiral carbonyl ylides with imine dipolarophiles as a route to enantiomerically pure α-amino-β-hydroxy acids
作者:Yu Gan、Laurence M. Harwood、Simon C. Richards、Ian E.D. Smith、Victoria Vinader
DOI:10.1016/j.tetasy.2009.02.029
日期:2009.5
The preparation of enantiomerically pure threo-β-amino-α-hydroxy acids via 1,3-dipolar cycloadditions of imine dipolarophiles with the chiral isomünchnone derived from (5R)-5-phenylmorpholin-3-one 1 is described. The cycloadducts were obtained with excellent diastereofacial- and exo-selectivity. Subsequent hydrolysis and chemoselective exocyclic amide cleavage afforded the threo-β-amino-α-hydroxy acids