Effective Darzen's condensation of 4-nonanolide with 1,6-dibromohexan-2-one using new bead-shaped insoluble multi-site (six-site) phase transfer catalyst and low concentration of aqueous NaOH
Murugan, E; Siva, A
| HERO ID | 854630 |
|---|---|
| In Press | No |
| Year | 2007 |
| Title | Effective Darzen's condensation of 4-nonanolide with 1,6-dibromohexan-2-one using new bead-shaped insoluble multi-site (six-site) phase transfer catalyst and low concentration of aqueous NaOH |
| Authors | Murugan, E; Siva, A |
| Journal | Journal of Molecular Catalysis A: Chemical |
| Volume | 277 |
| Issue | 1-2 |
| Page Numbers | 81-92 |
| Abstract | New bead-shaped insoluble polymer-supported multi-site (six-site) phase transfer catalyst (BSIMPTC) was synthesized from mesitylene as a starting material and its catalytic efficiency was studied with the kinetics of Darzen's condensation of 4-nonanolide with 1,6-dibromohexan-2one. The presence of six active-sites in the newly synthesized BSIMPTC, viz., 2,4,6-tris[(4-(2,2'-bis(N-triethylammoniummethylene chloride) eth-1-ene) phenoxy)benzene was characterized through FT-IR, solid H-1 NMR, C-13 NMR, SEM and [chloride ion] analyses and found that the BSIMPTC contains approximate to 6 active-site centers. The Darzen's condensation reaction of 4-nonanolide was performed at lower temperature (40 degrees C) under pseudo-first order rate conditions by taking lower concentration of aqueous NaOH (15 %, w/v, 3.75 M) and excess of 1,6-dibromohexan-2-one. The disappearance of 4-nonanolide was quantitatively monitored by a gas chromatograph for the calculation of the pseudo-first order rate constant. The presence of more number of active-sites in BSIMPTC was further confirmed from the comparative study of pseudo-first order rate constant with the rate constants of single-site polymer-supported phase transfer catalyst. The comparative rate constant results reveal that the BSIMPTC is highly active-than the corresponding soluble six-active-site and almost approximate to 4 times higher active-than with insoluble/soluble single-site PTCs. The effect of various experimental parameters such as [substrate], [catalyst], [NaOH], stirring speed, and temperature on the rate of the reaction have also been studied and found that each variables are influenced the rate of reaction. Based on the obtained kinetic results, a suitable mechanism is proposed. (C) 2007 Elsevier B.V. All rights reserved. |
| Doi | 10.1016/j.molcata.2007.07.023 |
| Wosid | WOS:000250983200011 |
| Url | http://linkinghub.elsevier.com/retrieve/pii/S1381116907004220 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Language Text | English |
| Keyword | phase transfer catalyst; 4-nonanolide; oxirane; multi-site; interfacial; polymer supported; triphase catalysts; Darzen's condensation |
| Is Qa | No |