52687-80-6Relevant academic research and scientific papers
Influence of the reaction temperature on the regioselectivity in the rhodium-catalyzed hydroformylation of vinylpyrroles
Caiazzo, Aldo,Settambolo, Roberta,Uccello-Barretta, Gloria,Lazzaroni, Raffaello
, p. 279 - 284 (1997)
The influence of the temperature on the regioselectivity in the hydroformylation of the vinylpyrrole isomers and of the corresponding N-tosylated substrates has been investigated in the range 20-100°C, in the presence of Rh4(CO)12. At all the temperatures the branched aldehyde was prevailing with respect to the linear isomer for all the substrates ( α-regioselectivity). With increasing temperature, an increase of the linear aldehyde was observed to a different extent in dependence on the substrate nature. 2H NMR investigation of the crude reaction mixture recovered from deuterioformylation of 3-vinylpyrrole at partial substrate conversion points out that the observed depression of the α-regioselectivity with increasing temperature must be connected to a β-hydride elimination process occurring for the branched alkyl-rhodium intermediates but not for the linear ones.
High α-regioselectivity in the rhodium-catalyzed hydroformylation of vinylpyrroles
Settambolo, Roberta,Caiazzo, Aldo,Lazzaroni, Raffaello
, p. 337 - 338 (2007/10/02)
The Rh4(CO)12-catalyzed hydroformylation at low temperature (40°C) of the 1-, 2- and 3-vinylpyrrole gives the corresponding branched aldehydes 2-(1-pyrrolyl)propanal, 2-(2-pyrrolyl)propanal and 2-(3-pyrrolyl)propanal with high α-regioselectivity.
Synthesis and Stereoselective Reactions of 2-(Pyrrol-1-yl)alkanals and 2-(pyrrol-1-yl)alkan-1-ones
Kashima, Choji,Maruyama, Tatsuya,Fujioka, Yoko,Harada, Kazuo
, p. 1041 - 1046 (2007/10/02)
2-(2,5-Dimethylpyrrol-1-yl)alkanals, 2-(pyrrol-1-yl)alkanals, and 2-(2,5-dimethylpyrrol-1-yl)alkan-1-ones were prepared.The reactions of these compounds with Grignard and hydride reagents proceeded stereoselectively to give the corresponding 2-(pyrrol-1-yl)alcohols, which were converted into 2-aminoalcohols, such as norephedrine and ephedrine, by cleavage of the pyrrole ring.
