Enantioselective Syntheses of 2-Deoxyxylono-1,4-lactone and 2-Deoxyribono-1,4-lactone from 1,3-Dioxan-5-yl Diazoacetates
作者:Michael P. Doyle、Jason S. Tedrow、Alexey B. Dyatkin、Coenraad J. Spaans、Doina G. Ene
DOI:10.1021/jo991211t
日期:1999.11.1
95% ee but with the mirror image configuration of that produced from the trans-2-(tert-butyl) analogue. The catalysts that are most suitable for these carbon-hydrogen insertion reactions are chiral dirhodium(II) carboxamidates. 1,3-Dialkoxy-2-propyl diazoacetates give mainly 2-deoxyxylono-1,4-lactone derivatives (>90:10) with generally high enantiocontrol, but replacement of hydrogen at the 2-position
1,3-二恶烷-5-基重氮乙酸酯是用于高度非对映选择性和对映选择性碳氢插入反应的有价值的底物。反式-2-(叔丁基)-1,3-二恶烷-5-基重氮乙酸酯是2-脱氧核糖-1,4-内酯的直接前体,其ee含量高达81%,而顺式2-(叔丁基) )-1,3-二氧杂-5-基重氮乙酸酯仅产生高达96%ee的受保护的2-deoxyxylono-1,4-lactone。但是,反式-2-芳基-1,3-二恶烷-5-基重氮乙酸酯(芳基=苯基或2-萘基)可形成2-deoxyxylono-1,4-lactone的前驱体,但可达95%ee,但带有镜反式-2-(叔丁基)类似物产生的图像构型。最适合于这些碳-氢插入反应的催化剂是手性氨基甲酸酯二氨基(II)。1,3-二烷氧基-2-丙基重氮乙酸酯主要产生2-deoxyxylono-1,4-lactone衍生物(> 90: