Atropisomeric Properties of <i>N</i>-Acyl/<i>N</i>-Sulfonyl 5<i>H</i>-Dibenzo[<i>b</i>,<i>d</i>]azepin-7(6<i>H</i>)-ones
作者:Takuya Namba、Mayuno Hotta、Hidetsugu Tabata、Kosho Makino、Tetsuta Oshitari、Hideaki Natsugari、Hideyo Takahashi
DOI:10.1021/acs.joc.1c00594
日期:2021.6.4
exocyclic bond (axis 3) is not in concert with the endocyclic axes (axis 1, axis 2). For the preparation of 5H-dibenzo[b,d]azepin-7(6H)-one, the intramolecular Friedel–Crafts acylation of N-(1,1′)-biphenyl-2-yl-glycine derivatives was revisited. It was revealed that the electron-withdrawing property of the amino-protective group was a key to the success of seven-membered cyclization.
的立体化学Ñ酰基/ Ñ磺酰5 ħ -二苯并[ b,d ]氮杂-7-(6 ħ) -酮(我,II)通过在C-4与冷冻甲基构象详细审查二苯并氮杂。由于两个轴(轴 1,轴 2)一起移动,I和II仅作为一对对映异构体 [(a 1 R , a 2 R ) 和 (a 1 S , a 2 S )] 存在,这已被证实通过IIBc 的X 射线分析. 阐明了酰胺衍生物I与E / Z-酰胺 (100:2–100:34)平衡存在,这意味着环外键(轴 3)与环内轴(轴 1,轴 2)。为了制备 5 H-二苯并[ b , d ] azepin-7(6 H )-one,重新审视了N -(1,1')-联苯-2-基-甘氨酸衍生物的分子内 Friedel-Crafts 酰化。结果表明,氨基保护基团的吸电子特性是七元环化成功的关键。