Unusual [3+1] Cycloaddition of a Stable Silylene with a 2,3-Diazabuta-1,3-diene versus [4+1] Cycloaddition toward a Buta-1,3-diene
作者:Yun Xiong、Shenglai Yao、Matthias Driess
DOI:10.1021/om901034w
日期:2010.2.22
N-heterocyclic silylene LSi: 1 L = CH[(C═CH2)CMe][N(Ar)]2], Ar = 2,6-iPr2C6H3} with acetone azine (1,1,4,4-tetramethyl-2,3-diazabuta-1,3-diene) and buta-1,3-diene derivatives have been probed. Unexpectedly, acetone azine undergoes a unique [3+1] cycloaddition to give the 1-sila-2,3-diazacyclobutane 2 and its 1-sila-2,3-diazacyclobutane isomer 3. The latter rearranges further to decrease ring strain,
热稳定的N-杂环亚甲硅基LSI的环加成反应:1 L = CH [(C = CH 2)CME] [N(Ar)的] 2 ]中,Ar = 2,6-我镨2 ç 6 ħ 3 }与已探究了丙酮嗪(1,1,4,4-四甲基-2,3-二氮杂丁-1,3-二烯)和丁1,3-二烯衍生物。出乎意料的是,丙酮嗪经过独特的[3 + 1]环加成反应生成1-sila-2,3-二氮杂环丁烷2及其1-sila-2,3-二氮杂环丁烷异构体3。后者进一步重排以降低环应变,得到相应的1-sila-4,5-二氮杂环己基-3-ene 4。相反,反应1与等电子2,3-二甲基丁-1,3-二烯提供预期的[4 + 1]环加成产物silacyclopentane 5。新的化合物2 - 5进行光谱表征,其中包括的单晶X-射线分析2,4,和5。