19550-40-4

Upstream product

• 74-85-1 ethene 
• 592-46-1 hexa-2,4-diene 
• 3809-32-3 2,5-dimethylcyclohexanol 
• 932-51-4 2,5-dimethylcyclohexanone 
• 917-64-6 methyl magnesium iodide 
• 21592-97-2 cis-4-methylcyclohex-2-en-1-ol 
• 21592-97-2 (±)-(1R*,4R*)-4-methylcyclohex-2-enol 
• 108667-06-7 (+/-)-toluene-4-sulfonic acid-(2t,5c-dimethyl-cyclohex-r-yl ester) 
• 7560-64-7 4-methyl-cyclohex-3-enecarbaldehyde 
• 78-79-5 isoprene 
• 5194-51-4 (2E,4E)-hexa-2,4-diene 
• 75-16-1 methylmagnesium bromide 

Downstream Products

• 1692-53-1 1-chloro-2-pentafluorosulfanylcyclohexane 
• 106-42-3 para-xylene 

Relevant academic research and scientific papers

Selective production of bio-based: Para -xylene over an FeOx -modified Pd/Al2O3catalyst

para-Xylene (PX) is a basic building block of polyethylene terephthalate, which is currently produced from petroleum resources. Developing a renewable route to PX is highly desirable to address both economic and environmental concerns. Several attempts used noble metal catalysts, e.g. Pd/Al2O3, to synthesize PX from biomass-derived 4-methyl-3-cyclohexene-1-carboxaldehyde (4-MCHCA), but suffered from a severe decarbonylation reaction, resulting in toluene as the main product. In this paper, we report an FeOx modification strategy to suppress the decarbonylation reaction on a Pd/Al2O3 catalyst, leading to a drastic shift in selectivity towards PX with a yield up to 81percent via a cascade dehydroaromatization-hydrodeoxygenation (DHA-HDO) pathway. Characterization and control experiments revealed that the electron density of Pd sites decreased in an FeOx-modified Pd/Al2O3 catalyst compared to Pd/Al2O3, thus tuning the preferential adsorption mode of the substrate from η2-(C,O), the key transition state of the decarbonylation reaction, to the η1-(O) mode that favors the hydrodeoxygenation process. Notably, this designed catalyst is highly stable and is readily applicable in the selective synthesis of a broad range of desired aromatic chemicals via the same DHA-HDO pathway from cyclohex-3-enecarbaldehyde derivatives. Overall, this work develops a controllable catalyst modification strategy that tailors an efficient catalyst for petroleum-independent bio-PX synthesis.

METHODS OF PREPARING PARA-XYLENE FROM BIOMASS

Methods or preparing para-xylene from biomass by carrying out a Diels-Alder cycloaddition at controlled temperatures and activity ratios. Methods of preparing bio- terephthalic acid and bio-poly(ethylene terephthalate (bio-PET) are also disclosed, as well as products formed from bio-PET.

SYNTHESIS OF PARA-XYLENE AND TOLUENE

A method of making para-xylene or toluene is carried out by: (a) reacting a C5 or C6 linear monoene (itself, or formed from a C5 or C6 linear alkane) with a hydrogen acceptor in the presence of a hydrogen transfer catalyst to produce a C5 or C6 diene; (b) reacting the C5-C6 diene with ethylene to produce a cyclohexene having 1 or 2 methyl groups substituted thereon; and then (c) either (i) dehydrogenating the cyclohexene in the presence of a hydrogen acceptor with a hydrogen transfer catalyst to produce a compound selected from the group consisting of para-xylene and toluene, or (ii) dehydrogenating the cyclohexene in the absence of a hydrogen acceptor with a dehydrogenation catalyst, to produce para-xylene or toluene.

Quantitative analyses of the seven isomeric 3,4- and 3,6-dimethylcyclohexenes by gas chromatography

Quantitative analyses of mixtures of the seven isomeric 3,4- and 3,6-dimethylcyclohexenes have been achieved by gas chromatography. Correlations of structure and absolute stereochemistry with elution order have been made rigorously with the aid of authentic optically active samples all derived from (3R)-methylcyclohexanone.