Formaldehyde, formyl

Formaldehyde—Formyl hydrid—H,COH—30—is formed when air charged with vapor of luethylic alcohol is passed over an incandescent platinum wire. It is also produced by the dry distillation of calcium formiate (HCOO)jCa = CaCOj-t-HCOH. It has not been obtained pure, but is known in solution in methyl alcohol. 

The yield of the more active RRR-a-tocopherol can be improved by selective methylation of the other tocopherol isomers or by hydrogenation of a-tocotrienol (25,26). Methylation can be accompHshed by several processes, such as simultaneous halo alkylation and reduction with an aldehyde and a hydrogen haUde in the presence of staimous chloride (27), amino alkylation with ammonia or amines and an aldehyde such as paraformaldehyde followed by catalytic reduction (28), or via formylation with formaldehyde followed by catalytic reduction (29). 

Ozonization of A -steroids usually gives complex mixtures (however, see ref. 48). Ozonolysis became a practical step in the general synthesis of B-norsteroids with the discovery that added methanol" (or formaldehyde ) improves yields significantly. Thus, Tanabe and Morisawa prepared 5/ -hydroxy-6/ -formyl-B-norsteroids (74) from cholesterol acetate, dehydroepiandrosterone acetate and pregnenolone acetate in overall yields of 64-74% by the reaction sequence represented below. 

Formaldehyde-to-phenol ratios, 404 V-Formyl amines, 158 Fourier transform infrared (FTIR) spectrometry, 116, 300, 387, 407-408 Fradet, Alain, 17 Free-radical copolymerization, 59 Friedel-Crafts acrylation polymerization, 332-334... 

Pr)4, " borohydride-exchange resin,and formic acid. When the last is used, the process is called the Wallach reaction. Conjugated aldehydes are converted to alkenyl-amines with the amine/silica gel followed by reduction with zinc borohydride.In the particular case where primary or secondary amines are reductively methylated with formaldehyde and formic acid, the method is called the Esch-weiler-Clarke procedure. It is possible to use ammonium (or amine) salts of formic acid, " or formamides, as a substitute for the Wallach conditions. This method is called the Leuckart reaction,and in this case the products obtained are often the N-formyl derivatives of the amines instead of the free amines. Primary and secondary amines can be iV-ethylated (e.g., ArNHR ArNREt) by treatment with NaBH4 in acetic acid. Aldehydes react with aniline in the presence of Mont-morillonite KIO clay and microwaves to give the amine. Formaldehyde with formic acid converts secondary amines to the N-methyl derivative with microwave irradiation. 

The formylation of P-H bonds in mono and multiprimary phosphines, which result in the formation of hydroxymethyl phosphines, is among the facile useful reactions in organophosphorus chemistry. As shown in Scheme 9, formaldehyde in the presence of platinum catalysts transforms P-H bonds into hydroxymethyl (P-CHjOH) functionahties (Scheme 9) [52]. 

Recent studies in our laboratory have demonstrated that formylation of P-H bonds can be achieved without the aid of transition metal catalysts under mild reaction conditions [47]. For example, amide and thioether functionalized primary phosphines, 5 and 9 respectively, upon treatment with 37% formaldehyde produced the corresponding amide/thioether functionaUzed water soluble phosphines 21 and 22 respectively in near quantitative yield (Scheme 10) [47]. 

Ab initio molecular orbital calculations are being used to study the reactions of anionic nucleophiles with carbonyl compounds in the gas phase. A rich variety of energy surfaces is found as shown here for reactions of hydroxide ion with methyl formate and formaldehyde, chloride ion with formyl and acetyl chloride, and fluoride ion with formyl fluoride. Extension of these investigations to determine the influence of solvation on the energy profiles is also underway the statistical mechanics approach is outlined and illustrated by results from Monte Carlo simulations for the addition of hydroxide ion to formaldehyde in water. 

Fluorenecarboxylic acid, 33, 37 Formaldehyde, 30, 51 33, 72 a-Formylethyl methyl ketone, 32, 34 Formyl isobutyl ketone, 32, 34 Friedel-Crafts reaction, 30, 1 31, 88 32, 10... 

Dimethylaminobenzaldehyde has been prepared previously from dimethylaniline, formaldehyde, and />-nitrosodimethylani-line in 56-59% yield,3 by the formylation of dimethylaniline with A-methylformanilide in approximately 50% yield,4 and by the formylation of dimethylaniline with dime thylformamide.6... 

The photooxidation of acrylonitrile by hydroxyl radicals in the presence of nitric oxide has been observed to yield formaldehyde (HCHO) and formyl cyanide (HCOCN) (Hashimoto et al. 1984). 

The corresponding reaction with formaldehyde gave HOs3(OMe)(CO)10, and this is thought to occur via the bridged formyl compound, R = H. 

Fahey (16) suggests that intermediate 3 dissociates formaldehyde he finds supportive evidence in the rhodium-based system by observation of minor yields of 1,3-dioxolane, the ethylene glycol trapped acetal of formaldehyde. For reasons to be discussed later, we believe the formation of free formaldehyde is not on the principal reaction pathway. (c) We have also rejected two aspects of the reaction mechanism proposed by Keim, Berger, and Schlupp (15a) (i) the production of formates via alcoholysis of a formyl-cobalt bond, and (ii) the production of ethylene glycol via the cooperation of two cobalt centers. Neither of these proposals accords with the observed kinetic orders and the time invariant ratios of primary products. 

Recently, the enzymatic formation of folinic acid has been utilized to synthesize radioactively labeled products.34 The preparation of 5-formyl tetrahydrofolate, 9,3, 5 -3H and 5-formyl-14C-tetrahydrofolate starts with tritiated folic acid, which is reduced to dihydrofolate, incubated in the presence of formaldehyde, dihydrofolate reductase, and NADPH, and finally incubated with 5,10-methylenetetrahydrofolate dihydrogenase. The product,... 

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