Preparation of Bis(diazo) Compounds Incorporated into Butadiyne and Thiophene Units, and Generation and Characterization of Bis(carbene) From These Compounds
作者:Tetsuji Itoh、Fumika Morisaki、Katsuyuki Hirai、Hideo Tomioka
DOI:10.1021/jo0494026
日期:2004.9.1
(1−N2) was found to be stable enough to survive under Sonogashira and Suzuki coupling reaction conditions, and bis(diazo) compounds incorporated into the 1,4-positions of butadiyne (3−2N2) and the 2,5-position of thiophene (4−2N2) were prepared. Irradiation of those bis(diazo) compounds generated bis(carbenes), which were characterized by ESR and UV−vis spectroscopic techniques in a matrix at low temperature
发现[9- 10-(4-叔丁基-2,6-二甲基)苯基}蒽基](4-溴-2,6-二甲基苯基)重氮甲烷(1- N 2)足够稳定,可以在以下条件下生存制备了Sonogashira和Suzuki偶联反应条件,以及在丁二炔的1,4-位(3 -2N 2)和噻吩的2,5-位(4 -2N 2)中掺入的双(重氮)化合物。这些双(重氮)化合物的辐照产生了双(卡宾),其在低温下通过ESR和紫外可见光谱技术在基质中以及室温下在溶液中的时间分辨紫外可见光谱进行了表征。这些研究表明,双(卡宾)3和在图4中,具有单重态单峰双自由基基态,其非常小的单重态-三重态能隙小于1 kcal / mol。与单碳烯(1)相比,双(碳烯)的寿命显着增加,并被解释为表明,由于未成对电子在整个π-网架上的离域作用,使双(碳烯)在热力学上稳定了。尽管具有稳定性,两种双(卡宾)仍容易被分子氧捕获,从而以双(酮)为主要产物。