Propanal condensation with formaldehyde

A third homogeneously catalyzed process, on the basis of formaldehyde condensation with propanal to give methacrolein and subsequent oxidation to methacrylic acid, was commercialized in 1990 by BASF. Application of this process is limited by the availability of cheap propanal, produced by large-scale ethylene hydroformylation (cf. Section 2.1.1). 

Metriol trinitrate can be prepared by nitration of methyltrimethylol-methane (Metriol) with mixed acid. Metriol is prepared by condensation of propanal with formaldehyde in a manner similar to that employed in the synthesis of pentaerythrol. 

In addition 1,3-dithians can be converted into carbonyl compounds thus, l,3dithiacyclohexane (18) (obtained by condensation of propane-1,3-dithiol and formaldehyde) can be alkylated with 3-chloroiodopropane (iodine is the more reactive halide and is selectively displaced) to yield eventually cyclobutanone (19) by the sequence shown in Scheme 4. This sequence shows the stabilising influence of the two adjacent... 

This installation was also used for the oxidation of methane—propane mixtures, since it was demonstrated in laboratory experiments that the yield of formaldehyde in the oxidation of propane is 2.5—2.7 times higher than in the oxidation of methane imder similar conditions. Experiments were carried out with an 80% CH4—20% CsHg hydrocarbon mixture. The hydrocarbon-air working mixture contained 67 vol % air and was fed at a flow rate of 150 m /h The yield of formaldehyde was 4.4 vol % with respect to the sum of the hydrocarbons, i.e., 1.8 times greater than for the oxidation of CH4 under the same conditions. The number of moles of water formed per mole of formaldehyde was higher than for the oxidation of methane alone, so the concentration of the solution obtained by formaldehyde condensation was below 30—35 wt% as compared to 40—45 wt% for the oxidation of methane [196]. 

Ethyl propane-1 1 3 3-tetracarboxylate. Cool a mixture of 320 g. (302 ml.) of redistilled diethyl malonate and 80 g. of 40 per cent, formaldehyde solution ( formalin ) contained in a 1-htre round-bottomed flask to 5° by immersion in ice, and add 5 g. (7 ml.) of diethylamine. Keep the mixture at room temperature for 15 hours and then heat under a reflux condenser on a boiling water bath for 6 hours. Separate the aqueous layer, dry the organic layer with anhydrous magnesium sulphate, and distil under reduced pressure. Collect the ethyl 1 1 3 3-tetracarboxylate at 200-215°/20 mm. The yield is 250 g. 

Bakelite Polymer produced by condensation of phenol and formaldehyde first by Leo Baekeland, bifnnctional Molecule with two active functional groups, bisphenol A 2,2 -bis(4-hydroxphenol)propane. 

Prepn is by nitrating trimethyl-propane (obtained by condensing formaldehyde with butyraldehyde in the presence of lime) with a mixt of nitric and sulfuric acids... 

The telechelica,(i -bis(2,6-dimethylphenol)-poly(2,6-dimethylphenyl-ene oxide) (PP0-20H) [174-182] is of interest as a precursor in the synthesis of block copolymers [175] and thermally reactive oligomers [179]. The synthesis has been accomplished by five methods. The first synthetic method was the reaction of a low molecular weight PPO with one phenol chain end with 3,3, 5,5 -tetramethyl-l,4-diphenoquinone. This reaction occurred by a radical mechanism [174]. The second method was the electrophilic condensation of the phenyl chain ends of two PPO-OH molecules with formaldehyde [177,178], The third method consists of the oxidative copolymerization of 2,6-dimethylphenol with 2,2 -di(4-hydroxy-3,5-di-methylphenyl)propane [176-178]. This reaction proceeds by a radical mechanism. A fourth method was the phase transfer-catalyzed polymerization of 4-bromo-2,6-dimethylphenol in the presence of 2,2-di(4-hy-droxy-3,5-dimethylphenyl)propane [181]. This reaction proceeded by a radical-anion mechanism. The fifth method developed was the oxidative coupling polymerization of 2,6-dimethylphenol (DMP) in the presence of tetramethyl bisphenol-A (TMBPA) [Eq. (57)] [182],... 

The capping of N3S3-semiclathrochelate [Co(ten)]3+ cation via a template-assisted mixed aldehyde (formaldehyde/propanal) condensation (Scheme 47) made it possible to obtain NsSs-sarcophaginates with both regular and contracted cavities in fairly high yield, as well as to isolate the corresponding free ligands [124]. 

Peracetic acid and formaldehyde are the expected ozonolysis products for acetone enol (6), and they are obtained in roughly equimolecular ratio. Infrared spectra cannot be used to identify them since peracetic acid in propan-2-ol absorbs at 1755 cm. , coinciding with a minor solvent peak, while formaldehyde monomer would presumably exist as hemi-acetal. Peracetic acid does not survive gas chromatography at 40 °C. on a polypropylene oxide/glycerol condensate (GPO-50)-glutaric acid phase. However, the peracid titer partitioned between trichlorofluoro-... 

U.S. production of w-butanol has increased to 600 kt per annum, largely for conversion to unsaturated esters and saturated ester and ether solvents, while 2-ethylhexanol (about 300 kt per annum in the U.S., but much higher in Europe with exports at 250 kt per annum) is used mainly for the phthalate ester as a plasticizer for PVC. The n- and iso-butyraldehydes are also subjected to aldol condensation/crossed Cannizzaro reactions with formaldehyde, to give the polyols trimethylol-propane (2, 2-bishydroxymethyl-l-butanol) and neopentyl glycol (2,2-dimethyl-1,3-propanediol). 

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