5509-14-8Relevant academic research and scientific papers
Benzocyclobutadienes: An Unusual Mode of Access Reveals Unusual Modes of Reactivity
Xiao, Xiao,Woods, Brian P.,Xiu, Wen,Hoye, Thomas R.
, p. 9901 - 9905 (2018)
The reaction of an aryne with an alkyne to generate a benzocyclobutadiene (BCB) intermediate is rare. We report here examples of this reaction, revealed by Diels–Alder trapping of the BCB by either pendant or external electron-deficient alkynes. Mechanistic delineation of the reaction course is supported by DFT calculations. A three-component process joining the benzyne first with an electron-rich and then with an electron-poor alkyne was uncovered. Reactions in which the BCB functions in a rarely observed role as a 4π diene component in Diels–Alder reactions are reported. The results also shed new light on aspects of the hexadehydro-Diels–Alder reaction used to generate the benzynes.
Gold-Catalyzed Cadiot–Chodkiewicz-type Cross-Coupling of Terminal Alkynes with Alkynyl Hypervalent Iodine Reagents: Highly Selective Synthesis of Unsymmetrical 1,3-Diynes
Li, Xiangdong,Xie, Xin,Sun, Ning,Liu, Yuanhong
supporting information, p. 6994 - 6998 (2017/06/08)
A new and efficient method for the synthesis of unsymmetrical 1,3-butadiynes by gold-catalyzed C(sp)–C(sp) cross-coupling of terminal alkynes with alkynyl hypervalent iodine(III) reagents has been developed. The reaction features high selectivity and efficiency, mild reaction conditions, wide substrate scope, and functional-group compatibility, and is a highly attractive complement to existing methods. Mechanistic studies reveal that formation of a phenanthrolinyl-ligated gold(I) complex is crucial for the efficiency and selectivity of the target transformation.
