Synthesis of 9-Fluorenylidenes via Pd-Catalyzed C–H Vinylation with Vinyl Bromides
作者:Shuai Yang、Yanghui Zhang
DOI:10.1021/acs.orglett.1c02722
日期:2021.10.15
A facile and efficient approach for the synthesis of 9-fluorenylidenes has been developed via the palladium-catalyzed cross-coupling of 2-iodobiphenyls and vinyl bromides. The reaction involves the C–H activation of 2-iodobiphenyls and dual C–C bond formations. A range of 9-fluorenylidene derivatives, including diphenyldibenzofulvenes, can be synthesized with the reaction.
protocol for the construction of 9-(diorganomethylidene)fluorenes through palladium-catalyzed coupling reactions of 2-iodobiphenyls with alkenyl bromides has been reported. The reaction proceeds through the C–H activation/oxidative addition/reduction elimination/intramolecular Heck coupling reaction to afford a series of 9-(diorganomethylidene)fluorenes with good yields. Control experiments demonstrate that
Synthesis of Benzo[<i>b</i>]fluoranthenes and Spiroacridines from Fluorene-Derived Alkenes and <i>N</i>-Arylimines via a Tandem Reaction with Benzynes
作者:Weihua Wang、Hongwei Wan、Guangfen Du、Bin Dai、Lin He
DOI:10.1021/acs.orglett.9b00659
日期:2019.5.17
Two tandem processes involving the cycloaddition of benzynes have been developed for the synthesis of polyaromatic hydrocarbons. Benzynes react with fluorene-derived alkenes through a tandem Diels–Alder reaction/dehydrogenation process to afford benzo[b]fluoranthenes in 35–87% yields. In addition, an unprecedented [2 + 2] cycloaddition/ring-opening sequence of benzynes and fluorene-derived N-arylimines
已经开发了涉及联苯的环加成的两个串联方法来合成聚芳族烃。通过串联Diels-Alder反应/脱氢过程,苯并zy与芴衍生的烯烃反应,以35-87%的收率得到苯并[ b ]芴。此外,前所未有的[2 + 2]苯并炔和芴衍生的N-芳基嘧啶的环加成/开环顺序可轻松获得螺cr啶,收率为38-79%。
An N-heterocyclic carbene-catalyzed switchable reaction of 9-(trimethylsilyl)fluorene and aldehydes: chemoselective synthesis of dibenzofulvenes and fluorenyl alcohols
作者:Yu-Chuan Ma、Jin-Yun Luo、Shi-Chu Zhang、Shu-Hui Lu、Guang-Fen Du、Lin He
DOI:10.1039/d1ob00065a
日期:——
carbene-catalyzed synthesis of dibenzofulvenes and fluorenyl alcohols was developed. In the presence of 10 mol% NHC (1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) and 4 Å molecular sieves, 9-(trimethylsilyl)fluorene undergoes an olefination reaction with aldehydes to produce dibenzofulvenes in 43–99% yields. However, on reducing the NHC loading to 1 mol% and with the addition of water, 9-(trimethylsilyl)fluorene
Potassium Fluoride Supported on Alumina Induced Aldol Condensation of Fluorene
作者:Wen-xing Lu、Chao-guo Yan、Rong Yao
DOI:10.1080/00397919608003789
日期:1996.10
In the presence of potassium fluoride supported on alumina as a solid base, Fluorene condensated smoothly with aromatic aldehydes in DMF at 150 degrees C to give dibenzofulvenes in fail yield (44-90%).