2]octa‐2,5‐dienes (bod*) 2 (Fig. 1) were tested as ligands in Rh‐catalyzed arylation reactions. The 1,4‐addition of arylboronic acids to cyclohex‐2‐en‐1‐one, cyclopent‐2‐en‐1‐one, and tert‐butyl cinnamate proceeded smoothly with excellent enantioselectivities (up to 99% ee; Tables 1–3). The challenging 1,2‐addition of triphenylboroxine to N‐[(4‐nitrophenyl)sulfonyl]imines yielded the product in high yield
在Rh催化的芳基化反应中,测试了一组十个C 1对称的手性双环[2.2.2] octa-2,5-二烯(bod *)2(图1)。将芳基
硼酸1,4加成到环己2烯1合一,环戊2烯1合1和
肉桂酸叔丁酯上时,对映选择性很好(至多ee为99%;表1 – 3)。在N -[(4-
硝基苯基)磺酰基]
亚胺中富挑战性地将三苯基环
硼氧烷1,2加成后,该产品收率高,对映选择性高(ee高达92%;表4)。通常,使用C 1带有大取代基的对称对称手性bod *
配体导致较低的对映选择性,而几种贫电子和富电子的bod *
配体具有比文献报道的基准
配体更高的对映选择性。