Reductive ring opening of dihydrodibenzothiepine and dihydrodinaphtho-oxepine and -thiepine
作者:Francisco Foubelo、Benjamín Moreno、Tatiana Soler、Miguel Yus
DOI:10.1016/j.tet.2005.07.042
日期:2005.9
hydrolysis, to unsymmetrically 2,2′-disubstituted binaphthyls 9 and 12, respectively. When the lithiation is performed with an excess of lithium in the presence of a catalytic amount of DTBB (10% molar), a double reductive cleavage takes place to give the dianionic intermediate VII, which by reaction with different electrophiles [H2O, Me2CO, Et2CO, (CH2)4CO, (CH2)5CO], followed by hydrolysis with water, yields
在-78°C下,4,4'-二叔丁基联苯(DTBB)催化的二氢二苯并噻吩平(1)的锂化反应30分钟,然后与羰基化合物[ t BuCHO,Ph(CH 2)2 CHO,PhCHO,在相同温度下的(n -C 5 H 11)2 CO,(CH 2)5 CO,(CH 2)7 CO,(-)-薄荷酮]在用3 M盐酸水解后会生成硫烷基醇2。如果在添加羰基化合物作为第一亲电子试剂后[Me 2 CO,(CH 2)5CO,(-)-薄荷酮],使生成的II型二价阴离子在室温下反应30分钟,进行第二次锂化反应,生成III型中间体,该中间体通过与第二个亲电试剂[Me 2 CO ,Et 2 CO,(CH 2)5 CO,ClCO 2 Et],水解后得到苯基4的双官能团。硫烷醇2c在酸性条件下的环化反应产生八元含硫杂环3。二氢二萘并异庚烷7和10的锂化在−78°C的条件下用2.2当量的萘二甲酸锂在THF中反应,然后与不同的亲电试剂[H