fulltext.study @t Gmail

The reaction of pyrrole with dimethyl carbonate under phosphazene catalysis: N-methoxycarbonylation vsN-methylation

Paper ID Volume ID Publish Year Pages File Format Full-Text
47749 46481 2009 9 PDF Available
Title
The reaction of pyrrole with dimethyl carbonate under phosphazene catalysis: N-methoxycarbonylation vsN-methylation
Abstract

Phosphazene (t-butylimino-tris(dimethylamino)phosphorane (P1-t-Bu), t-butylimino-tris(pyrrolidino)phosphorane (BTPP)) and amidine (1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)) superbases have been investigated as catalysts in the direct reaction of pyrrole with dimethyl carbonate (DMC). The system phosphazene/pyrrole/DMC proves to be a flexible synthetic tool, as it offers a solution not only for the direct and selective phosgene-free synthesis of 1-methoxycarbonyl pyrrole (1), but also for the straightforward and selective synthesis of 1-methylpyrrole (2) through a safer way which avoids the use of harmful methylating agents such as methyl halides and (MeO)2SO2. The influence of factors (temperature, catalyst loading, reaction time, etc.) affecting yields and selectivities has been investigated. We have also ascertained that a major reaction pathway to the formation of 2 involves the decarboxylation of the primary product 1. Also this process was catalytically promoted by the phosphazene catalyst. Co-generated CO2 opened a way to the deactivation of phosphazene catalyst, which converted mainly into catalytically inactive OP(NR2)3 (NR2 = NMe2, NC4H8).

Keywords
Dimethyl carbonate; Pyrrole; Carbamate; Methoxycarbonylation; Alkylation; Organo-catalysts
First Page Preview
The reaction of pyrrole with dimethyl carbonate under phosphazene catalysis: N-methoxycarbonylation vsN-methylation
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Applied Catalysis B: Environmental - Volume 91, Issues 1–2, 7 September 2009, Pages 380–388
Authors
, , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Catalysis
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us