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Gold(i)-catalyzed nucleophilic cyclization of β-monosubstituted o-(alkynyl)styrenes: a combined experimental and
Cintia Virumbrales1, Marta Solas, Samuel Suárez-Pantiga
1Área de Química Orgánica, Departamento de Química, Facultad de Ciencias, Universidad de Burgos, Pza. Misael Bañuelos, s/n, 09001 Burgos, Spain. rsd@ubu.es.
Abstract:
The stereospecific gold(i)-catalyzed nucleophilic cyclization of β-monosubstituted o-(alkynyl)styrenes to produce C-1 functionalized 1H-indenes including challenging substrates and nucleophiles, such as β-(cyclo)alkyl-substituted o-(alkynyl)styrenes and a variety of alcohols as well as selected electron-rich aromatics, is reported. DFT calculations support the stereochemical outcome of the process that involves the formation of a key cyclopropyl gold carbene intermediate through a regiospecific 5-endo cyclization.
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