Brønsted Acid-Promoted Intramolecular Carbocyclization of Alkynals Leading to Cyclic Enones
Carlos González-Rodríguez, Luz Escalante, Jesús A. Varela, Luis Castedo and Carlos Sáa*
*Departamento de Química Orgánica, Facultad de Química,
Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain, Email:
carlos.saa
usc.es
C. González-Rodríguez, L. Escalante, J. A. Varela, L. Castedo, C. Sáa, Org. Lett., 2009, 11, 1531-1533.
DOI: 10.1021/ol900142r
Abstract
TFA-promoted exo carbocyclizations of nonterminal alkynals gave good to excellent yields of exo cycloalkenones. On the other hand, terminal 5-alkynals gave endo carbocyclizations to cyclohexenones. These carbocyclizations can be considered as tandem alkyne hydration/aldol condensation processes.
see article for more examples
Ru-Catalyzed Cyclization of Terminal Alkynals to Cycloalkenes
J. A. Varela, C. González-Rodríguez, S. G. Rubín, L. Castedo, Carlos Saá, J. Am. Chem. Soc., 2006, 128, 9576-9577.
Key Words
endo Cyclohexenones, Cyclopentenes, Cyclohexenes, Cycloheptenes
ID: J54-Y2009-1050
