Synthesis and [4+2] Cycloaddition of (2R,2′R)-N,N′-Fumaroylbis[fenchane-8,2-sultam] (=(2E)-1,4-Bis[(3aS,6S,7aR)-1,4,5,6,7,7a-hexahydro-7,7-dimethyl-2,2-dioxido-3H-3a,6-methano-2,1-benzothiazol-1-yl]but-2-ene-1,4-dione) to Cyclopentadiene
作者:Anna M. Piątek、Agnieszka Chojnacka、Christian Chapuis、Janusz Jurczak
DOI:10.1002/hlca.200590181
日期:2005.9
derivative (−)-5d. Also the N-methyl- and N-acryloylfenchane-8,2-sultams (−)-5b,c were prepared, and both the reactivity and diastereoselectivity imparted by the new chiral auxiliary to N,N′-fumaroylbis[fenchane-8,2-sultam] (−)-5e were compared with those of (−)-1a by addition of cyclopenta-1,3-diene to (−)-5e, in various solvents and at different temperatures under TiCl4-mediated and uncatalyzed conditions
将现在校正的(2 R)-硼烷-10,2-sultam((-)- 1a)的X射线结构及其已发表的N-巴豆酰基衍生物(-)- 1d的X射线结构与这些结构进行了比较新合成的(2 R)-fenchane-8,2-sultam((+)- 5a)及其N-巴豆酰基衍生物(-)- 5d的合成。还制备了N-甲基-和N-丙烯酰胺基戊烷-8,2-sultams(-)- 5b,c,并且新的手性助剂赋予了N,N反应性和非对映选择性。通过在不同溶剂中和在不同溶剂中向(-)- 5e中添加环戊-1,3-二烯环戊-1,3-二烯,将'-富马酰基双[fenchane-8,2-sultam](-)- 5e与(-)- 1a进行了比较TiCl 4介导和未催化条件下的温度。这些因素的影响来确定通过的损失合理化蒙面Ç 2由热力学不太稳定的溶剂对称性较早归因于樟脑衍生的磺内酰胺以及过渡态稳定偶极顺- S-顺式构象异构体。