title: The multicomponent Hantzsch reaction: comprehensive mass spectrometry monitoring using charge-tagged reagents.
abstract: A novel strategy for the ESI-MS monitoring of reaction solutions involving the alternate use of permanently charge-tagged reagents has been used for comprehensive mass spectrometry monitoring of the multicomponent Hantzsch 1,4-dihydropyridine reaction. By placing a charge tag on either, or both, of the two key reactants, ion suppression effects for ESI were eliminated or minimized, and comprehensive detection of charge-tagged intermediates was achieved. The strategy allowed the trapping and characterization of the important intermediates in the mechanism for 1,4-dihydropyridine formation.
authors.affiliation: ThoMSon Mass Spectrometry Laboratory, Instituto de Química, State University of Campinas, 13084-971, Campinas-SP (Brazil).
authors.forename: Vanessa G
authors.initials: VG
authors.lastname: Santos
authors.forename: Marla N
authors.initials: MN
authors.lastname: Godoi
authors.forename: Thaís
authors.initials: T
authors.lastname: Regiani
authors.forename: Fernando H S
authors.initials: FH
authors.lastname: Gama
authors.forename: Mirela B
authors.initials: MB
authors.lastname: Coelho
authors.forename: Rodrigo O M A
authors.initials: RO
authors.lastname: de Souza
authors.forename: Marcos N
authors.initials: MN
authors.lastname: Eberlin
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Garden
keywords: charge tags; electrospray ionization; ionic intermediates; multicomponent reactions; reaction mechanisms