fulltext.study @t Gmail

Synthesis and characterization of a novel multi-site phase transfer catalyst and a kinetic study of the intramolecular cyclopentanation of indene

Paper ID Volume ID Publish Year Pages File Format Full-Text
42858 45944 2009 8 PDF Available
Title
Synthesis and characterization of a novel multi-site phase transfer catalyst and a kinetic study of the intramolecular cyclopentanation of indene
Abstract

An easy access to a hitherto unknown novel multi-site catalyst viz., 1,3,5-tris(benzyltriethylammonium bromide)benzene (TBTABB) is delineated from low cost starting materials. The structures of the synthesized MPTC's and spiro indene derivative were evidenced by 1H NMR, 13CNMR, IR and elemental analysis. The potentiality of the new multi-site phase transfer catalyst was demonstrated by following the kinetics of the cyclopentanation of indene under pseudo-first order conditions by employing aqueous sodium hydroxide and 1,4-dibromobutane in excess. The kinetics of cyclopentanation of indene was carried out at low temperature (40 °C) and was monitored by gas chromatography. Further, the catalytic efficiency of the TBTABB was compared with those of the disite and single-site catalysts by investigating the kinetics of various cyclopentanation reactions. In examining six kinds of phase transfer catalyst, we found TBTABB to be highly efficient. The investigation considered the effects of various experimental parameters and conditions, including agitation speed, concentration of catalyst, concentration of substrate, concentration of sodium hydroxide and temperature on the rate of the reaction. The effect of multi-site phase transfer catalysts on the reaction rate is studied. From the Arrhenius plot, the activation energy was found to be 14.18 kcal mol−1. Thermodynamic parameters such as ΔS#, ΔG# and ΔH# were also evaluated. Utilizing the kinetic and thermodynamic results, we have proposed an interfacial mechanism for the cyclopentanation of indene. From the different experiments it can be concluded that TBTABB has great potential as a multi-site phase transfer catalyst.

Graphical abstractAn easy access to a hitherto unknown novel multi-site catalyst viz., 1,3,5-tris(benzyltriethylammonium bromide)benzene (TBTABB) is delineated from low cost starting materials. The potentiality of the new multi-site phase transfer catalyst was demonstrated by following the kinetics of the cyclopentanation of active methylene compounds under identical conditions. Based on the experimental results, a suitable mechanism is proposed.Figure optionsDownload full-size imageDownload as PowerPoint slide

Keywords
Phase transfer catalysis; Catalytic activity; Cyclopentanation; Indene; Kinetics; Multi-site; Interfacial mechanism
First Page Preview
Synthesis and characterization of a novel multi-site phase transfer catalyst and a kinetic study of the intramolecular cyclopentanation of indene
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 A: General - Volume 364, Issues 1–2, 31 July 2009, Pages 27–34
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