Mesitylene from acetone

Formation of mesitylene from acetone corresponds to that of mesityl oxide from acetone. 

Removal of water from certain compounds is often used for synthesis of aromatic rings. Adams and Hufferd977 obtained mesitylene from acetone by treatment with sulfuric acid, and Lyle et al.91s give the following generalized procedure for preparation of 1,3,5-triarylbenzenes ... 

Some examples of the addition of one carbonyl compound to another are the aldol condensation the formation of acetoacetic ester the condensation of benzaldehyde with one of the components of a mixture of an acid anhydride and a carboxylate salt the formation of mesityl oxide, phoroiie, and mesitylene from acetone and the condensations of aromatic aldehydes and ketones. Acids and bases are generally catalysts for these reactions. They have sufficient in common to warrant their being classed together as the aldol type of... 

Mesitylene can be synthesized from acetone by catalytic dehydrocyclization (17). Similarly, cyclotrimerization of acetylenes has produced PMBs such as hexamethylbenzene (18). Durene has been recovered from Methanex s methanol-to-gasoline (MTG) plant in New Zealand (19). 

Mesitylene, production from acetone, 1 164 Mesityl oxide, 14 589-590 characteristics of, 16 337 hydrogenation, 16 337-338 hydrogen peroxide treatment of, 16 338 Z-menthol from, 24 520 production of, 16 336-337 production from acetone, 1 164, 174 Mesogenic diols, 25 460 Mesogenic molecules, solids of, 15 82 Mesogens, 24 53, 54 Mesomixing, 16 683 Mesomorphic behavior, 24 53-54 Mesomorphic phase transitions, 15 102 Mesomorphism, 15 81. See also Liquid crystalline materials Mesophase pitch-based carbon fiber, 26 734-735... 

J. pr., 15,129.)—This is a reaction of historical interest, for it was by the preparation from acetone by distillation with fairly strong sulphuric acid that the symmetry of mesitylene was deduced, and hence the orientation of such compounds as m-xylene was established. 

If you work through this book from beginning to end your impression may be that aromatic compounds can be synthesized in many ways, but that one always starts from aromatic compounds. This is the case. Nonetheless, it may occasionally be advantageous to obtain an aromatic from a non-aromatic compound. This is demonstrated in Figure 12.12 using a synthesis of mesitylene (B) from acetone as an example. The mechanism comprises many individual... 

Synthesis of Mesitylene from Allylene.—The second proof of the symmetrical structure of mesitylene is its synthesis from allylene and also from acetone. The synthesis from allylene has already been spoken of in connection with the proofs of the structure of benzene (p. 478), and is exactly analogous to the synthesis of benzene by the polymerization of acetylene. 

From Acetone.—By treating acetone, CH3—CO—CHs, with concentrated sulphuric acid, water is eliminated, polymerization takes place similar to that in the above reactions, and mesitylene is obtained. The reaction is represented as follows ... 

Mesitylene, C6H3(CH3)3(1, 3, 5), symmetrical trimethyl-benzene, is found in coal-tar. It boils at 164.5° and has the specific gravity 0.8694 ( ). The hydrocarbon is most readily obtained by the action of concentrated sulphuric acid on acetone. If the two substances are mixed and distilled after standing some time, mesitylene is obtained. The yield is small, being from 10 to 20 per cent of that calculated from the weight of acetone used. The reaction consists in the removal of water from acetone —... 

Formation of mesitylene from three molecules of acetone. Source Kekule, Zeitschrift fiir Chemie 0 (1867) 215. 

Complexes of formula [() -arene)Rh(CO)L]PF6 (arene = CeHe, CeHsCFs, CeHsOMe, mesitylene, l,3,5-(MeO)3C6H3 L = PPP3) are readily formed by displacement of the weakly bound solvent from [Rh(COE)(L)(acetone)2] PFe by the arene, and the COE ligand can be then replaced by the more strongly bonding alkene ethylene. Treatment... 

Self-condensation of acetone was carried out at 473 K and 100 kPa in a flow system with a differential fixed-bed reactor. Acetone was vaporized in H2 (H2/acetone =12) before entering the reaction zone. The standard contact time (6fc) was 0.84 g of cat h/g of acetone. Main reaction products were mesityl oxides (MO s), isophorone (IP) and mesitylene (MES). Traces of phorone and light hydrocarbons were also identified. The coke formed on the catalysts was characterized after reaction, ex-situ, in a temperature-programmed oxidation (TPO) unit. The TPO experiments were carried out in a microreactor loaded with 50 mg of catalyst and using a 3 % O2/N2 carrier gas. Sample temperature was increased linearly from room temperature to 973 K at 10 K/min. The reactor exit gases were fed into a methanator operating at 673 K to convert CO in methane and then analyzed by flame ionization detector. 

A long series of researches on what Baeyer called condensation reactions began with a study of the action of acids on acetone, in which he worked out the conditions for the formation of mesityl oxide and phorone, set out the mechanisms of the reactions and the constitution of the products, and gave a synthesis of mesitylene. He synthesised picoline and collidine from compounds of ammonia with acetaldehyde and acrolein. ... 

Keeping the beneficial role of bases for the progress of the catalytic reaction in mind, Spencer recommended amides as solvents [19]. Indeed, only in the presence of AfdV-dialkylated amides was C-C coupling observed. In other solvents such as THF, ethyl acetate, or acetone, preferentially methanol was formed. Based on these findings, Ezhova and coworkers [20] conducted a detailed kinetic study in mesitylene/DMAA (DMAA=AfdV-dimethylacetamide) as solvent. It was found that the initial rate of the hydroformylation of formaldehyde is dependent on the concentration of an anionic complex with the general structure [Rh(CO)2(PPh3) (DMAA) ]. It can be formed from the Wilkinson complex or other precatalysts shown in Scheme 6.119 in a syngas atmosphere [21]. Under the effect of the protonated base, formaldehyde can add to this anionic complex with the formation of the hydroxymethyl—rhodium complex and the catalytic cycle proceeds. The reaction follows first-order kinetics. Under neutral conditions, a dimeric rhodium complex was observed. 

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