Cationic gold vinyl carbene/allylic cation complexes of the form (E)-[(L)AuC(H)C(H)CAr2]+ OTf− L = IPr, Ar = Ph [(E)-5a], L = IPr, Ar = 4-C6H4OMe [(E)-5b], L = P(t-Bu)2o-biphenyl, Ar = 4-C6H4OMe [(E)-5c]} were generated in solution via Lewis acid-mediated ionization of the corresponding gold (γ-methoxy)vinyl complexes (E)-(L)AuC(H)C(H)C(OMe)Ar2 at or below −95 °C. Complexes (E)-5b and (E)-5c were
( E )-[(L)AuC(H)C(H)CAr 2 ] + OTf - L = IPr, Ar = Ph [( E )- 5a ], L形式的阳离子金乙烯基卡宾/烯丙基阳离子配合物= IPr, Ar = 4-C 6 H 4 OMe [( E )- 5b ], L = P( t -Bu) 2邻联苯, Ar = 4-C 6 H 4 OMe [( E )- 5c ]}通过路易斯酸介导的相应金 (γ-甲氧基) 乙烯基络合物 ( E )-(L)AuC(H)C(H)C(OMe)Ar 2的电离在溶液中产生-95 °C 或以下。配合物 ( E )- 5b和 ( E )- 5c在溶液中使用多核 NMR 光谱进行了充分表征,这确定了金烯丙基阳离子共振结构的主要贡献以及正电荷在 γ-茴香环中的显着分布。配合物 ( E )- 5b在 -95 °C 下与仅在乙烯基卡宾部分的 C1 位上的中性双电子、氢化物和氧原子
Diarylamino Groups as Photostable Auxofluors in 2-Benzoxazolylfluorene, 2,5-Diphenyloxazoles, 1,3,5-Hexatrienes, 1,4-Distyrylbenzenes, and 2,7-Distyrylfluorenes
作者:Joel M. Kauffman、Guillermo Moyna
DOI:10.1021/jo020333+
日期:2003.2.1
The relationship of structure to optical spectral properties was determined for five types of fluors in a search for an optimum-wavelength shifter to be used as part of the detection systems for high-energy particles from accelerators. In a search for photostable fluors to serve as waveshifters in plastic fibers it was found that the wavelengths of interest, absorption max 410 +/- 10 nm and fluorescence
Catalytic Reactions of Carbene Precursors on Bulk Gold Metal
作者:Yibo Zhou、Brian G. Trewyn、Robert J. Angelici、L. Keith Woo
DOI:10.1021/ja900653s
日期:2009.8.26
Bulk gold metal powder, consisting of particles (5-50 microm) much larger than nanoparticles, catalyzes the coupling of carbenes generated from diazoalkanes (R(2)C=N(2)) and 3,3-diphenylcyclopropene (DPCP) to form olefins. It also catalyzes cyclopropanationreactions of these carbeneprecursors with styrenes. The catalytic activity of the gold powder depends on the nature of the gold particles, as
散装金金属粉末,由比纳米粒子大得多的粒子 (5-50 微米) 组成,催化重氮烷烃 (R(2)C=N(2)) 和 3,3-二苯基环丙烯 (DPCP) 产生的卡宾的耦合形成烯烃。它还催化这些卡宾前体与苯乙烯的环丙烷化反应。金粉的催化活性取决于金颗粒的性质,这由 TEM 和 SEM 研究确定。可以从涉及生成卡宾 R(2)C:吸附在金表面上的中间体的机制来理解这些反应。
Synthese von Δ<sup>2</sup>-Dihydro-muconsäure und von Tetraphenylhexatrien aus<i>d,l</i>-β-Oxyadipinsäure
作者:M. Viscontini、H. Köhler
DOI:10.1002/hlca.19540370106
日期:——
Die Herstellung von β-Methoxy-adipinsäure aus β-Ketoadipinsäure wird beschrieben. Der β-Methoxy-adipinsäure-dimethylester kann durch eine Grignard'sche Synthese in 1,1,6,6-Tetraphenyl-3-methoxy-hexandiol-(1,6) und hierauf in Tetraphenylhexatrien umgewandelt werden.