Acrylic acid methanation

The formation of spirocyclopropanes from the reaction of diazodiphenylmethane and ( )-8-phenylmenthyl esters of acrylic acid and methyl fumarate occurred with a modest level of diastereofacial selectivity (136). In contrast, diastereoselectivities of 90 10 were achieved in the cycloadditions of diazo(trimethylsilyl)methane with acrylamides 65 derived from camphor sultam as the chiral auxiliary (137) (Scheme 8.16). Interestingly, the initial cycloadducts 66 afforded the nonconjugated A -pyrazolines 67 on protodesilylation the latter were converted into optically active azaproline derivatives 68. In a related manner, acrylamide 69 was converted into A -pyrazolines 70a,b (138). The major diastereoisomer 70a was used to synthesize indolizidine 71. The key step in this synthesis involves the hydrogenolytic cleavage of the pyrazoline ring. 

One of the most important challenges in the modern chemical industry is represented by the development of new processes aimed at the exploitation of alternative raw materials, in replacement of technologies that make use of building blocks derived from oil (olefins and aromatics). This has led to a scientific activity devoted to the valorization of natural gas components, through catalytic, environmentally benign processes of transformation (1). Examples include the direct exoenthalpic transformation of methane to methanol, DME or formaldehyde, the oxidation of ethane to acetic acid or its oxychlorination to vinyl chloride, the oxidation of propane to acrylic acid or its ammoxidation to acrylonitrile, the oxidation of isobutane to... 

Figure 2 Selectivity at 30% conversion for the reactions indicated as a function ofD°H C-H(reactant) - D°HC-h or c-c (product). 1 ethylbenzene to styrene 2. 1-butene to 1, 3-butadiene 3. toluene to benzoic acid 4. acrolein to acrylic acid 5. ethane to enthylene 6. n-butane to maleic anhydride 7. benzene to phenol 8. toluene to benzaldehyde 9. propene to acrolein 10. 1-butene to 2-butanone 11. isobutene to isobutene 12. methanol to formaldehyde 13. methacrolein to methacyclin acid 14. propane to propene 15. ethanol to acetaldehyde 16. isobutene to methacrolein 17. n-butane to butene 18. benzene to maleic anhydride 19. propane to acrolein 20. methane to ethane 21. ethane to acetaldehyde, 22. isobutane to methacrylic acid 23. methane to formaldehyde 24. isobutane to methacrolein.

The smino acids used hy Blicke and Gould -were all secondary amines obtained by the addition of benzylamiue or alkyl amines to atropic acid or other substituted acrylic acids. The acid chloride salts v ore prepared by treatment with thionyl chloride, and after removing by-products the crude products were r cxed in bensene solution with excess dimethylaniline. The 1.8- and 1,4-disuhstituted azetidinones were isolated in yields of 40 80%, The benefioial influenoe of substitution was observed with the l-benzyl-S-methyl 4-phenyl- and l-benxyl-.S,3-dim thyl-4 phenyl-2-azetidinones, both of which were obtained in 90% yield. In an unsbooeasfu) attempt to prepare -aminodiasoketonea several of the acid chloride hydrochlorides were treated with diaxo-methane this reaction also fumishes the /9-laotams, although in rather low yield. 

Figure 3 Selectivity in product versus D H c-H reactant D°H c-H or C-C product at 30% conversion. 1, Ethylbenzene to Styrene. 2, 1-Butene to Butadiene. 3, Acrolein to Acrylic Acid. 4, Ethane to Ethylene. 5, n-Butane to Maleic Anhydride. 6, Propene to Acrolein. 7, Methanol to Formaldehyde. 8, Ethanol to Acetaldehyde. 9, Propane to Propene. 10, n-Butane to Butenes. 11, Propane to Acrolein. 12, Methane to Ethane. 13, Ethane to Acetaldehyde. 14, Methane to Formaldehyde [1].

The benzoic acid might also be made by the Diels-Alder reaction of 1,3-butadiene with acrylic acid followed by catalytic dehydrogenation. Treatment of phenol with ammonia at high temperatures produces aniline, as mentioned in Chap. 2. Ethylbenzene can be rearranged to xylenes with zeolite catalysts. Thus, it could serve as a source of ph-thalic, isophthalic, and terephthalic acids by the oxidation of o, m, and p-xylenes. (The xylenes and other aromatic hydrocarbons can also be made by the dehydrocyclization of ethylene, propylene, and butenes, or their corresponding alkanes.44 Benzene can also be made from methane.195)... 

A dinickel(I) compound 17 was made from the reaction between metallacyclic Ni(n) carboxylate ( nickelalactone ) and bis(diphenylphosphino)methane (dppm) (Scheme 10.7) [11]. The Ni(I)-Ni(I) bond length in 17 is 2.563(1) A (Entry 4, Table 10.2), and features three different bridging ligands (dppm, carboxylate, diphenylphosphido). The formation of 17 was proposed to proceed via the mechanism depicted in Scheme 10.8, and is remarkable because it acts as a model for the key step in the formation of acrylic acid from COj and ethylene. 

In a typical 400 MHz H-NMR spectra of low-conversion S-AA bulk copolymer dissolved in deuterated dimethyl sulfoxide (DMSO-Dg) and in DMSO-Dg-CDCl3 at 50 °C, the chemical shift of different protons, respectively, are 1-2 ppm for all methane protons and the methylene proton of the styrene emits in the copolymer chain 2.3 ppm for the methylene proton of the acrylic acid emit in the copolymer chain 3.3 ppm for water in DMSO-Dg, 5.2-6.4 ppm multi-peaks for the end groups of the copolymer chains that may be double bonds and isobntylnitrile 6.4-7.4 ppm for aromatic protons and 12.1 for the proton of the carboxyl gronp on the copolymer chain. 

With respect to the catalytic reactions, there are well-established industrial reactions (as occurs in the case of n-butane to maleic anhydride), reactions in the preindustrial stage (such as the transformation of propane to acrylonitrile), very promising reactions (such as ethane oxidative dehydrogenation to ethylene), and potential reactions whose economical viability will depend on the prices of crude and natural gas in the future (such as propane selective oxidation to acrylic acid or methane transformation). 

Experiments under static conditions gave liquid products containing various oxygenates, such as methanol, ethanol, acetaldehyde, acetic acid, -propanol, isopropanol, propionalde-hyde, acetone, acrolein, propionic acid, and acrylic acid. The gas phase contained methane, ethane, and ethylene. The conversion of propane ranged from 15% to 61% at a total selectivity of up to 15% to liquid oxygenates and 10% to Ci—C2 hydrocarbons. 

Acrylic acid, HCI, H2O, CO, CO2, acryloyl cbloride, methyl acrylate, 262 methyl acrylate chain fragments, anhydride and y-lactone stractures, chloro-methane, methyl methacrylate, methanol, 3,5-(6-chloro-2-pyrone) and fragments thereof C, C9, C 12, C 15 fragments. Relative yields depend upon copolymer composition... 

Questions are still asked about the role of DMS, which is sometimes seen, along with DMSP as having an antioxidant function in marine algae because the breakdown products of DMSP (i.e., DMS, acrylate, dimethylsulfoxide, and methane sulfinic acid) readily scavenge hydroxyl... 

SULFICYLBIS (METHANE) (67-68-5) CjHjOS (CH3)2S0 Combustible liquid [explosion limits in air (vol %) 2.6 to 63.0 flashpoint 203°F/95°C oc autoignition temp 419°F/215°C Fire Rating 2]. Violent or explosive reaction with strong oxidizers, acryl halides, aryl halides and related compounds, alkali metals p-bromobenzoyl acetanilide, boron compounds, especially hydrides iodine pentafluoride, magnesium perchlorate, methyl bromide, perchloric acid, periodic acid, silver fluoride, sodium hydride, potassium permanganate. Forms powerfully explosive mixtures with metal salts of oxoacids [iron(III)nitrate, phosphonic acid, sodium perchlorate]. On small fires, use dry chemicals or COj extinguishers. 

The next most important demand for methyl alcohol is as a raw material in the synthesis of many important organic compounds, including formaldehyde acetic acid chloro-methanes, compounds in which the hydroxyl group and/or one or more hydrogen has been replaced by fluorine, chlorine, bromine, and/or iodine methyl methacrylate, a compound from which acrylic plastics are made methylamines, the source of another important class of plastics, dimethyl terephthalate, the monomer for yet another class of plastics and other products. 

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