866462-83-1Relevant academic research and scientific papers
Group 4 Diarylmetallocenes as Bespoke Aryne Precursors for Titanium-Catalyzed [2 + 2 + 2] Cycloaddition of Arynes and Alkynes
Reiner, Benjamin R.,Tonks, Ian A.
, p. 10508 - 10515 (2019)
Despite the ubiquity of reports describing titanium (Ti)-catalyzed [2 + 2 + 2] cyclotrimerization of alkynes, the incorporation of arynes into this potent manifold has never been reported. The in situ generation of arynes often requires fluoride, which instead will react with the highly fluorophilic Ti center, suppressing productive catalysis. Herein, we describe the use of group 4 diarylmetallocenes, CpR2MAr2 (CpR = C5H5, C5Me5; M = Ti, Zr), as aryne precursors for the Ti-catalyzed synthesis of substituted naphthalenes via coupling with 2 equiv of an alkyne. Fair-to-good yields of the desired naphthalene products could be obtained with 1% catalyst loadings, which is roughly an order of magnitude lower than similar reactions catalyzed by palladium or nickel. Additionally, naphthalenes find broad applications in the electronics, photovoltaics, and pharmaceutical industries, urging the discovery of more economic syntheses. These results indicate that aryne transfer from a CpR2M(?2-aryne) complex to another metal is a viable route for the introduction of aryne fragments into organometallic catalytic processes.
Synthesis, structure, and photophysical properties of highly substituted 8,8a-dihydrocyclopenta[a]indenes
Wu, Yao-Ting,Kuo, Ming-Yu,Chang, Yu-Ting,Shin, Chien-Chueh,Wu, Tsun-Cheng,Tai, Chia-Cheng,Cheng, Tzu-Heng,Liu, Wei-Szu
scheme or table, p. 9891 - 9894 (2009/05/07)
(Chemical Equation Presented) A triple round: A palladium-catalyzed cyclotrimerization of 1,2-diarylacetylenes has been developed to synthesize highly substituted 8,8a-dihydrocyclopenta[a]indenes. One such cycloadduct (1) displays unusual aggregation-induced emission with a strong blue fluorescence (see picture). The structures of the products have been confirmed by X-ray crystal analysis.
