Catalytic Co-Homologation of Alkanes and Dimethyl Ether and Promotion by Adamantane as a Hydride Transfer Co-Catalyst
نویسندگان
چکیده
Competitive reactions between C-labeled dimethyl ether (C-DME) and unlabeled alkenes have been used to examine the mechanistic details of chain growth and termination pathways leading to the selective formation of triptane and isobutane by means of the homologation of DME or methanol (Scheme 1). These studies have also provided specific and quantitative evidence for the ubiquitous role of carbenium-ion stability on the relative rates of competing reactions catalyzed by solid acids. Homologation of C1 reactants occurs at modest temperatures (400–500 K) through Brønsted acid catalyzed pathways mediated by carbenium ion transition states in homogeneous ZnI2 and InI3 [2–6] liquidphase systems and on acidic zeolites (ZSM-5, USY, BEA), 7] amorphous SiO2 Al2O3, and supported Keggin heteropolyacids (5 wt% H3PW12O40/SiO2). [8]
منابع مشابه
Selective homogeneous and heterogeneous catalytic conversion of methanol/dimethyl ether to triptane.
The demand for specific fuels and chemical feed-stocks fluctuates, and as a result, logistical mismatches can occur in the supply of their precursor raw materials such as coal, biomass, crude oil, and methane. To overcome these challenges, industry requires a versatile and robust suite of conversion technologies, many of which are mediated by synthesis gas (CO + H(2)) or methanol/dimethyl ether...
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