1238893-03-2Relevant academic research and scientific papers
Gold(I)-catalyzed cycloisomerizations and alkoxycyclizations of ortho-(alkynyl)styrenes
Sanjun, Ana M.,Rashid, Muhammad A.,Garca-Garca, Patricia,Martnez-Cuezva, Alberto,Fernndez-Rodrguez, Manuel A.,Rodrguez, Flix,Sanz, Roberto
, p. 3042 - 3052 (2015/02/05)
Indenes and related polycyclic structures have been efficiently synthesized by gold(I)-catalyzed cycloisomerizations of appropriate ortho-(alkynyl)styrenes. Disubstitution at the terminal position of the olefin was demonstrated to be essential to obtain products originating from a formal 5-endo-dig cyclization. Interestingly, a complete switch in the selectivity of the cyclization of o-(alkynyl)-a-methylstyrenes from 6-endo to 5-endo was observed by adding an alcohol to the reaction media. This allowed the synthesis of interesting indenes bearing an all-carbon quaternary center at C1. Moreover, dihydrobenzo[a]fluorenes can be obtained from substrates bearing a secondary alkyl group at the β-position of the styrene moiety by a tandem cycloisomerization/1,2-hydride migration process. In addition, diverse polycyclic compounds were obtained by an intramolecular gold-catalyzed alkoxycyclization of o-(alkynyl)styrenes bearing a nucleophile in their structure. Finally, the use of a chiral gold complex allowed access to elusive chiral 1H-indenes in good enantioselectivities.
Synthesis of thioacetal via AgOTf-catalyzed reaction of 2-alkynylbenzaldehyde with thiol
Wu, Ran,Gao, Shang,Yang, Guanghui,Pan, Lingling,Liu, Ming,Hu, Keyong,Zhong, Weihui,Yu, Chuanming
, p. 299 - 305 (2015/06/22)
An efficient and mild method for thioacetalization of 2-alkynylbenzaldehydes in the presence of a catalytic amount of silver triflate has been described. This reaction proceeded efficiently to generate 2-alkynylbenzaldehydes thioacetals in good to excellent yields at room temperature within short reaction time (no more than 30 min). This transformation was extremely easy to perform without the need of using anhydrous solvent and inert atmosphere. Chemoselective thioacetalization of benzaldehyde in the presence of acetophenone was also demonstrated.
