作者:Noboru Ono、Koji Matsumoto、Takuji Ogawa、Hiroyuki Tani、Hidemitsu Uno
DOI:10.1039/p19960001905
日期:——
A new synthesis of push-pull dienes such as 4-nitro-1-phenylthiopenta-1,3-diene 4 and 1-dialkylamino-4-nitropenta-1,3-diene 5, is described. The X-ray crystal analysis shows that 4-nitro-1-(pyrrolidin-1-yl)penta-1,3-diene 5a is essentially planar in an E,E-configuration with r(C–C)= 1.42(1)Å and r(CC)= 1.35(1) and 1.371(9)Å. Compounds 5 showed a large solvatochromic effects similar to that of merocyanine dyes. Molecule 5a exhibits second harmonic generation (SHG) activity whose efficiency is 2.5 times that of urea (determined by a powder method at 1064 nm). For 5a, the molecular nonlinearity µβ is estimated to be 1200 × 10–48 esu which is calculated from the Pockel coefficient (r33) determined by electrooptic measurements of poled polymers of 5a in poly(methyl methacrylate) at 1300 nm. This value is relatively large for such small conjugated molecules, where donors and acceptors are bridged by only 4π electron systems.
本文描述了一种新的推拉二烯合成方法,例如4-硝基-1-苯基噻吩五-1,3-二烯4和1-二烷基氨基-4-硝基五-1,3-二烯5。X射线晶体分析显示,4-硝基-1-(吡咯烷-1-基)五-1,3-二烯5a基本为平面E,E构型,r(C–C)=1.42(1)Å,r(CC)=1.35(1)和1.371(9)Å。化合物5表现出与金属氰染料类似的大的溶剂化效应。分子5a表现出二次谐波产生(SHG)活性,其效率是尿素的2.5倍(通过粉末法在1064 nm处测定)。对于5a,分子非线性µβ估计为1200 × 10–48 esu,这是从波克尔系数(r33)计算得出的,该系数是通过在1300 nm处对5a的极化聚合物在聚甲基丙烯酸甲酯中的电光测量确定的。这个值对于这种小的共轭分子来说是相对较大的,其中供体和受体仅通过4π电子系统连接。