160680-85-3Relevant academic research and scientific papers
Pyrrole and oligopyrrole synthesis by 1,3-dipolar cycloaddition of azomethine ylides with sulfonyl dipolarophiles
Robles-Machin, Rocio,Lopez-Perez, Ana,Gonzalez-Esguevillas, Maria,Adrio, Javier,Carretero, Juan Carlos
supporting information; experimental part, p. 9864 - 9873 (2010/11/16)
A procedure for the synthesis of functionalized, substituted pyrroles by 1,3-dipolar cycloaddition of azomethine ylides has been developed. This protocol is based on the metal-catalyzed cycloaddition of α-iminoesters with sulfonyl dipolarophiles, followed by the base-promoted elimination of the sulfonyl groups. A wide variety of 2,5-disubstituted and 2,3,5- and 2,4,5trisubstituted pyrroles have been prepared in satisfactory yields from 1,2bis(sulfonyl ethylene), ss-sulfonylenones, and ss- sulfonylacrylates. This method can be applied in an iterative and straightforward manner to the construction of oligopyrroles, from bipyrroles to pentapyrroles. Iterative [n+1] and [n+2] approaches have been devised, the latter involves double 1,3-dipolar cycloaddition from pyrrolylbased bis(iminoesters).
Oligopyrrole synthesis by 1,3-dipolar cycloaddition of azomethine ylides with bissulfonyl ethylenes
Lopez-Perez, Ana,Robles-Machin, Rocio,Adrio, Javier,Carretero, Juan Carlos
, p. 9261 - 9264 (2008/12/22)
(Chemical Equation Presented) One by one or two by two: In a general approach to the iterative construction of oligopyrroles, the cycloaddition of azomethine ylides derived from pyrrolyl α-iminoesters with 1,2-bis(phenylsulfonyl)-ethylene is followed by the elimination of the sulfonyl groups in situ under basic conditions. This strategy is amenable to the introduction of one or two pyrrole units in each iterative cycle.
