(Wiley-Blackwell, 2020) García Fernández, Pedro David; Izquierdo, Cristina; Iglesias Sigüenza, Francisco Javier; Díez Martín, Elena; Fernández Fernández, Rosario Fátima; Lassaletta, JM; Universidad de Sevilla. Departamento de Química orgánica; Ministerio de Economía y Competitividad (MINECO). España; Junta de Andalucía
The formal insertion of alkenes into aromatic chloro- and bromoalkynes takes place under cationic gold catalysis. This haloalkynylation reaction can be performed with cyclic, gem-disubstituted and monosubstituted alkenes, using BINAP, triazolo[4,3-b]isoquinolin-3-ylidene ligands or SPhos, respectively. The products were isolated in moderate to excellent yields and with complete diastereo- and regioselectivity; the halogen atom bonding the more substituted carbon of the alkene. Preliminary experiments showed that the enantioselective haloalkynylation of cyclopentene can be performed with (S)-BINAP to afford the insertion products with moderate to good enantioselectivities.
