A gold-catalyzed cascade reaction of skippeddiynes (1,4-diynes) and pyrroles has been developed. This reaction proceeds by the consecutive regioselective hydroarylation of two alkynes with a pyrrole, followed by a 7-endo-dig cyclization to give 1,6-dihydrocyclohepta[b]pyrroles in good yields. The direct synthesis of cyclohepta[b]indoles using indole nucleophiles has also been reported.
已经开发了金催化的二炔(1,4-二炔)和吡咯的级联反应。该反应通过用吡咯连续进行两个炔烃的区域选择性加氢芳基化反应,然后进行7-内-挖-环化得到高收率的1,6-二氢环庚[ b ]吡咯。也已经报道了使用吲哚亲核试剂直接合成环庚[ b ]吲哚。
768. Studies with acetylenes. Part II. Some reactions of Grignard reagents with propargylic halides. Model linoleic and linolenic acid systems
作者:S. S. Nigam、B. C. L. Weedon
DOI:10.1039/jr9570003868
日期:——
Schlubach; Repenning, Justus Liebigs Annalen der Chemie, 1958, vol. 614, p. 37,46
作者:Schlubach、Repenning
DOI:——
日期:——
Copper-Catalyzed Electrophilic Amination of Alkenylzirconocenes with <i>O</i>-Benzoylhydroxylamines: An Efficient Method for Synthesis of Enamines
作者:Xiaoyu Yan、Chao Chen、Yiqing Zhou、Chanjuan Xi
DOI:10.1021/ol302004t
日期:2012.9.21
Copper-catalyzed electrophilic amination of alkenylzirconocenes is accomplished under mild reaction conditions. The reaction tolerates a wide range of functional groups and can be used to prepare some hindered enamines.
Campo del Cielo iron meteorite: Sample shielding and meteoroid's preatmospheric size
作者:R. G. LIBERMAN、J. O. FERNÁNDEZ NIELLO、M. L. TADA、L. K. FIFIELD、J. MASARIK、R. C. REEDY
DOI:10.1111/j.1945-5100.2002.tb01111.x
日期:2002.2
Abstract— Long‐lived cosmogenic radioisotopes, 10Be, 26Al, 36Cl, 41Ca and 59Ni, have been measured in five samples from the Campo del Cielo iron meteorite by accelerator mass spectrometry (AMS). The 36Cl activities were significantly above the background. For the concentrations of the other four radioisotopes, only upper limits were obtained that were, however, consistent with the 36Cl result. The measured 36Cl activity allowed an estimate of the meteoroid's preatmospheric size: a radius larger than 300 cm and a mass of at least 840 000 kg. We conclude that this meteorite might be one of the largest meteorites to have been recovered.