Phthalyl alcohol

Powerful complex hydrides like lithium aluminum hydride in refluxing ether [5i] or refluxing tetrahydrofuran [1017] reduce cyclic anhydrides to diols. Phthalic anhydride was thus transformed to phthalyl alcohol (o-hydroxy-methylbenzyl alcohol) in 87% yield [5i]. Similar yields of phthalyl alcohol were obtained from phthalic anhydride and sodium bis 2-methoxyethoxy) aluminum hydride [544, 969]. 

Phthalyl alcohol, HOCH2CeH4CH20H-o. Mol. wt. 138.16, m.p. 64°. Prepared by reduction of phthalic anhydride with lithium aluminum hydride in ether (87% yield). In a novel and efficient synthesis of cyclopropanone hydrate, Grewe and Struve used the o-xylylene acetal protective group (1) and, after elimination of... 

Heating phthalyl alcohol (o-phenylenedimethanol) with a small amount of /7-toluenesulfonic acid gives the cyclic benzyl ether (phthalan)675 in about... 

Catalytic etherification in the gas phase can be exemplified by the preparation of phthalan from phthalyl alcohol 676... 

Molten phthalyl alcohol (276 g) is dehydrated by passing its vapor through a column filled with activated alumina and heated at 300° after distillation of the product in steam in the presence of 10% aqueous sodium hydroxide, phthalan is isolated in 89% yield (214 g). 

Ishikawa et al. have shown that the treatment of the diol (213) with perfluoro-2-methyl-2-pentene gives a good yield of the benzodioxonin (214), presumably via the intermediate (215) (Scheme 20). Phthalyl alcohol similarly gave the corresponding 1,5-benzodioxonin <8IJFC(18)447>. 

A mixture of bromacetaldehyde diethyl acetal and phthalyl alcohol containing a little p-toluenesulfonic acid heated slowly in an oil bath with distillation of the resulting ethanol during- ca. 45 min., finally under reduced pressure bromacetaldehyde o-xylylene acetal. Y S0%,—The protective group can be removed by catalytic hydrogenolysis. R. Grewe and A. Struve, B. 96, 2819 (1963). 

The modified procedure involves refluxing the N-substituted phthaUmide in alcohol with an equivalent quantity of hydrazine hydrate, followed by removal of the alcohol and heating the residue with hydrochloric acid on a steam bath the phthalyl hydtazide produced is filtered off, leaving the amine hydrochloride in solution. The Gabriel synthesis has been employed in the preparation of a wide variety of amino compounds, including aliphatic amines and amino acids it provides an unequivocal synthesis of a pure primary amine. 

Benzylatnine. Warm an alcoholic suspension of 118-5 g. of finely-powdered benzyl phthalimide with 25 g. of 100 per cent, hydrazine hydrate (CAUTION corrosive liquid) a white, gelatinous precipitate is produced rapidly. Decompose the latter (when its formation appears complete) by heating with excess of hydrochloric acid on a steam bath. Collect the phthalyl hydrazide which separates by suction filtration, and wash it with a little water. Concentrate the filtrate by distillation to remove alcohol, cool, filter from the small amount of precipitated phthalyl hydrazide, render alkaline with excess of sodium hydroxide solution, and extract the liberated benzylamine with ether. Dry the ethereal solution with potassium hydroxide pellets, remove the solvent (compare Fig. //, 13, 4) on a water bath and finally distil the residue. Collect the benzylamine at 185-187° the 3ueld is 50 g. 

A classical method for the preparation of a-amino aldehydes is the conversion of N -pro-tected a-amino acid chloride derivatives to aldehydes by hydrogenation in the presence of palladium on charcoal 15 or barium sulfate. 16 This method is especially used for the conversion of phthalyl-a-amino acid chlorides into the corresponding aldehydes. N -Protected amino acid chlorides or fluorides are also readily reduced by lithium tri-ferf-butoxyaluminum hydride1 7 at low temperature without epimerization, but this method is of limited application because overreduction into the respective alcohols also occurs. 

PVA is further modified to obtain polyvinylacetatephthalate (PVAcP), which is used in enteric coatings. PVAcP is prepared from the reaction of partially hydrolyzed polyvinyl alcohol, sodium acetate and phthalic anhydride. It consists of 55 to 62% of phthalyl groups. The PVA used is a low molecular weight grade with 87 to 89 mole% hydrolyzed. Since only vinyl alcohol portions of the partially hydrolyzed PVA are phthalated, the acetyl content remains constant before and after the reaction. 

This procedure required but one resolution of the acetylenic alcohol 40 which then served to resolve the remaining chiral portion of the molecule. The resolution of octyn-3-ol 40 therefore was the start of the synthesis of the optically active 7-oxaprostanoids. Reaction of the racemic octyn-3-ol 40 with phthalic anhydride gave the phthalyl acid 41 which formed the crystalline salt 42 by reaction with ( )-o -phenethylamine with the absolute configuration shown. 

An important feature of this invention consists in the preparation of anhydrous hydrazine by dissociating the anhydrous hydrazine salt of phthalyl hydrazide itself. This salt can be prepared in anhydrous condition by the addition of ethyl alcohol to an aqueous solution of phthalylhydrazide in excess hydrazine hydrate and drying the resultant precipitate. Heat treatment of the anhydrous salt up to 180°C. under a pressure of 0.05 mm. of mercury in a vacuum distillation apparatus connected to a receiver cooled to about -40°C. gives a 92% 3deld of anhydrous hydrazine. 

Alternatively, the required anhydrous salts may be obtained by reacting a phthalimide with about 2.5 molecular proportions of hydrazine hydrate in boiling ethyl alcohol until all the ammonia formed has been eliminated. From the reaction mixture a precipitate, consisting of the required phthalyl hydrazide salt of hydrazine, separates. Dissociation of the dried salt in the manner hereinbefore described yields the anhydrous hydrazine. 

Carbethoxy malaoxon. See Malaoxon Carbethoxy malathion. See Malathion Carbethoxymethyl diethyl phosphonate. See Triethyl phosphonoacetate Carbethoxymethyl ethyl phthalate. See Ethyl phthalyl ethyl glycolate p-Carbethoxyphenol. See Ethylparaben 3-Carbethoxypyridine. See Ethyl nicotinate Carbinamine. See Methylamine, aqueous solutions Methylamine Carbinol. See Methyl alcohol Carbinoxamide maleate. See Chloropheniramine maleate Carbital 35] Carbital 50] Carbital 75] Carbital 90. See Calcium carbonate Carbitol Carbitol . See Ethoxydiglycol Carbitol acetate Carbitol Acetate. See Ethoxydiglycol acetate... 

Butyl myristate Methyl cocoate Oleyl alcohol PEG-300 oleate PEG-300 stearate Propylene glycol myristate plasticizer, delayed tack latex 1,4-Cyclohexanedimethanol dibenzoate plasticizer, dental adhesives n-Butyl phthalyl-n-butyl glycolate plasticizer, dental compounds Carnauba (Copemica cerifera) wax plasticizer, dental impression compounds Japan (Rhus succedanea) wax plasticizer, deodorants Hexyldecyl benzoate plasticizer, depilatories Oxidized beeswax plasticizer, detergents PPG-20 lanolin alcohol ether plasticizer, dip parts Diphenyl octyl phosphate plasticizer, dopes Di butyl tartrate plasticizer, dry cleaning PEG-8 cocoate PEG-20 hydrogenated castor oil PEG-60 hydrogenated tallowate PEG-12 ricinoleate PEG-2 stearate PEG-2 tallowate plasticizer, elastomers Butyl acetyl ricinoleate Butyl cyclohexyl phthalate Dibutyl phthalate Dibutyl tartrate n-Dioctyl phthalate... 

Methoxypropyl formamide Methylamine N-Methylaniline Methyl behenate o-Methylbenzyl alcohol 2-Methyl-1-butanol Methyl caproate Methylcyclohexanol acetate N-Methylcyclohexylamine N-Methylethanolamine Methylhydrazine Methyl-(S)-lactate 3-Methylpentane Methyl phthalyl ethyl glycolate 1-Methylpiperidine 2-Methylpropanal Mixed terpenes Naphtha, heavy aliphatic Naphtha, heavy alkylate Naphtha, heavy aromatic Naphtha, hydrodesulfurized heavy Naphtha, hydrotreated heavy Naphtha, hydrotreated light Naphthalene Naphtha, light aliphatic Naphtha, light alkylate Naphtha, solvent-refined light Naphthenic acid Naphthol spirits Neoheptane... 

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