766-15-4Relevant academic research and scientific papers
Conversion of Isobutene and Formaldehyde to Diol using Praseodymium-Doped CeO2 Catalyst
Zhang, Zhixin,Wang, Yehong,Lu, Jianmin,Zhang, Chaofeng,Wang, Min,Li, Mingrun,Liu, Xuebin,Wang, Feng
, p. 8248 - 8254 (2016/12/14)
Conversion of low-carbon olefins to higher alcohols or olefins via the formation of C-C bonds is an increasingly important topic. We herein report an example of converting isobutene and formaldehyde (38 wt % aqueous solution) to 3-methyl-1,3-butanediol (MBD), a precursor for isoprene. The reaction occurs through a Prins condensation-hydrolysis reaction over a praseodymium (Pr)-doped CeO2 catalyst. The best MBD yield (70%) is achieved over the Pr-doped CeO2 catalyst. Catalyst characterizations with high-angle annular dark field transmission electron microscopy (HAADF-TEM), pyridine adsorption infrared (IR) and Raman spectroscopy, and density functional theory (DFT) calculations show that the doped Pr is uniformly and highly dispersed in the CeO2 crystalline phase. In addition, the Pr doping creates more oxygen vacancy sites on CeO2 and thus enhances the Lewis acidity of the catalyst, which is responsible for the catalytic performance of the Pr-CeO2 catalyst. (Chemical Equation Presented).
A comparative study of an MCM-41 anchored quaternary ammonium chloride/SnCl4 catalyst and its silica gel analogue
Jyothi,Kaliya,Herskowitz,Landau
, p. 992 - 993 (2007/10/03)
A novel reusable Lewis acid catalyst has been prepared by the heterogenization of a Lewis acid/tetrapropylammonium adduct; anchoring of tin chloride on quaternary ammonium chloride functionalized MCM-41 yielded a catalyst with higher activity compared to the corresponding silica analogue in terms of turnover rates and product yield in the Prins condensation of isobutene and formaldehyde to isoprenol.
A Lewis acid catalyst anchored on silica grafted with quaternary alkylammonium chloride moieties
Jyothi, Thundi M.,Kaliya, Mark L.,Landau, Miron V.
, p. 2881 - 2884 (2007/10/03)
Resistance to leaching and re-usability are characteristic of the novel heterogeneous Lewis acid catalyst that was prepared by anchoring tin(IV) chloride on silica grafted with tetraalkylammonium or pyridinium chloride groups. The catalyst displays high activity and selectivity in the synthesis of 3-methyl-3-buten-1-ol by the Prins condensation of isobutene with formaldehyde [Eq. (1)].
Isoprene by Prins condensation over acidic molecular sieves
Dumitriu,Trong On,Kaliaguine
, p. 150 - 160 (2007/10/03)
The Prins condensation of isobutylene with formaldehyde over different catalysts (HY, USY, H-ZSM-5, H-Boralite, H-B-MCM-41) having various pore sizes and acidities has been investigated in a pulse microreactor. The results show unambiguously that high sel
CONDENSATION OF ISOBUTENE WITH FORMALDEHYDE IN NITROMETHANE.
Zakoshanskii,Idlis
, p. 1769 - 1771 (2007/10/02)
It is shown that condensation of isobutene with formaldehyde in nitromethane proceeds at a high rate and selectivity. The qualitative and quantitative compositions of the products formed in water and in nitromethane indicate that the reaction mechanisms in the two media are different.
MECHANISM OF HYDROLYSIS OF 4,4-DIMETHYL-1,3-DIOXANE
Zakoshanskii, V. M.,Rybkina, L. A.,Gankin, V. Yu.,Idlis, G. S.
, p. 1727 - 1732 (2007/10/02)
The hydrolysis of 4,4-dimethyl-1,3-dioxane in aqueous solutions of sulfuric acid (4-40 wt. percent) and p-toluenesulfonic acid (3-50 wt. percent) was investigated at various temperatures.According to the proposed hydrolysis mechanism, the directions which determine the process rate are the monomolecular dissociation of the protonated molecules of the 1,3-dioxane and the dissociation of the intermediate particles consisting of the protonated molecules of 1,3-dioxane and the anions of the acid.The true values of the rate constants for each of the paths and their temperature dependence were determined.It was concluded that the variation of the effective activation energy with variation of the sulfuric acid concentration may be criterion for the occurence of the reaction in several directions, i.e., catalysis by several types of acid particles.
COCONDENSATION OF ISOBUTYLENE WITH FORMALDEHYDE AND ACETALDEHYDE
Safarov, M. G.,Ogorodnikov, S. K.,Ibatullin, U.G.,Idlis, G. S.,Nigmatullin, N. G.
, p. 805 - 809 (2007/10/02)
2,4,4-Trimethyl-1,3-dioxane is formed preferentially in the reaction of isobutylene, formaldehyde, and acetaldehyde in the presence of an acidic catalyst.In addition, 4-dimethyl- and 2,4,4,6-tetramethyl-1,3-dioxanes, 4-methyl-2,4-pentanediol and 3-methyl-1,3-butanediol were found in the reaction mass.The possibility of mutual transformations between the cyclic acetals and formal through the stage of the formation of consecutive-parallel reactions is proposed.
