Phenyl-acetic acid isothiocyanate

On the other hand, refluxing 9 in formic acid for 5 h afforded the N-formyl derivative 11 in high yield. Acetylation of 9 by refluxing in acetic acid, afforded acetic acid N -(2-(7-hydroxy-2-oxo-2H-chromen-4-yl)-acetyl)-hydrazide 12 in good yield. Compound 13 was also obtained by refluxing 9 with 3-(2-bromoacetyl)-4-hydroxy-2H-chromen-2-one in ethanol. Reaction of compound 9 with phenyl isothiocyanate in ethanol at room temperature gave 4-phenyl-1 - (7-hydroxy-2-oxo-2 H-chromen-4-acetyl- )thiosemicarbazide 14. 

Treatment of N-2,4-dinitrophenylpyridinium chloride (778) with phenyl-hydrazine in acetic acid causes reductive cyclization to yield the pyrido[l,2-ajimidazole (779). 3-Aminocrotononitrile, MeC(NH2)=CHCN, condenses with quinoline 1-oxide and isoquinoline 2-oxide to form the tricyclic compounds (780) and (781), respectively." The imidazo[5,l-a]isoquinoline derivative (783) is obtained by the action of phenyl isothiocyanate on the sodium salt of the Reissert compound (782)." ° Triethyl phosphite reduces the o-nitrophenyldipyr-rolylmethane (784 R=N02) to the nitrene (784 R = N), which forms the pyrrolo[3,2-6]quinoline derivative (785) by an intramolecular insertion reac-tion." 3-Amino-177-isoindole (786) reacts with acetylacetone in the presence of perchloric acid to yield the pyrimidoisoindolium salt (787). ... 

Dihydrazide 231 was also used in the synthesis of thienothiophenes containing triazole substituents. For example, the reaction with phenyl isothiocyanate in ethanol produces di(A -phenylthiocarbamoyl)carbohydrazide 238, whose treatment with KOH followed by acidification affords compound 239. Diazotization of dihydrazide 231 with 10% sodium nitrite in acetic acid gives diazide 240. The reactions of the latter with compounds containing the active methylene group, viz., ethyl cyanoacetate, malononitrile or diethyl malonate, in the presence of sodium ethoxide, yield the corresponding ditriazole derivatives 241-243. 

A standard condition has been optimized for this reaction, in which the aryl amine is diazotized in 10 times its amount of acetic acid, followed by the addition of one equivalent of cuprous halide in hydrohalic acid. Under these conditions, the acetate salt of aryl amine is relatively soluble, and less froth and tarry material are formed during diazo transformation. In addition, chlorination, bromination, and iodonation of p-haloaniline to dihalobenzenes under such standard conditions give almost comparable average yields. Other modifications of this reaction include the formation of phenyl selenocyanate by the reaction with potassium selenocyanate, and aryl nitrile by the reaction with nickel cyanide. Moreover, this reaction has been extended to the preparation of phenyl thiocyanate, phenyl isothiocyanate and aromatic sulfonyl chloride. ... 

Phenyl isothiocyanate, 619 N-Phenyllutidone, from dehydro-acetic acid and aniline,... 

Amino acid (0.5-1.0 g) is added to aqueous pyridine (1 1,25 ml) in a stoppered tube. The solution is adjusted to pH 9.0 with IN NaOH and placed in a water bath at 40°C. Phenyl isothiocyanate (1.2 ml) is added with shaking during a reaction time of about 30 min. Additional alkali is added to maintain the pH at 9. The mixture is extracted repeatedly with benzene to remove excess reagent and pyridine. When there is no further uptake of alkali, a slight excess of IN HCl is added to precipitate the PTC-amino acid. The mixture is filtered and warmed with HCl (IN, 30 ml) at 40 C for 2 h. The PTH-derivative crystallizes upon cooling, and further yields are obtained by concentration of mother liquors. Most of the derivatives are recrystallized from aqueous acetic acid or ethanol. 

N-[3 -(4-Methy Iphenyl)-1 -phenyl-1 H-pyrazol-4-methylidene] -cyanoacetic acid hydrazide 154 was synthesised in an excellent yield by condensing 3-(4-methylphenyl)- -phenyl-lH-pyrazole-4-carboxaldehyde with cyano-acetic acid hydrazide. This intermediate was converted to the 4-amino-3-aryl-5-[3-(4-methylphenyl)-1 -phenyl-1 H-pyrazol-4-methylidenehydrazinocarbonyl] -thiazole-2(3H)-thiones 155 (Scheme 72), following the method described by Gewald, it involved the reaction of the cyanoacetic acid hydrazide derivative 154 with sulphur and the appropriate aryl isothiocyanate in the presence of triethylamine as a basic catalyst. Cyclisation of 145 to the 3-aryl-6-[3-(4-methylphenyl)-l-phenyl-1 H-pyrazol-4-methylideneamino] -2-thioxo-2,3 -dihydrothiazolo [4,5 -djpyrimidin-7(6H)-ones 156 was achieved by heating the former with a mixture of triethyl orthoformate and acetic anhydride (1 1) [4],... 

Addition [of (213)] to the C=N bond of phenyl isothiocyanate and cyclization affords 5-arylidene-l-phenylrhodanines (216). The reaction of acrylic acids (213) with formaldehyde in acetic acid produces 4-arylidene-l,3-oxathiolan-5-ones (217), which are in their turn convertible by concentrated ammonia into 5-arylidenethiazolidin-4-ones (218). ... 

Phenyl isothiocyanate has been prepared from thiocarbanilide by the action of phosphorus pentoxide, hydrochloric acid, iodine, phosphoric acid, acetic anhydride, and nitrous acid. It has also been prepared from ammonium phenyl dithiocarbamate by the action of ethyl chlorocarbonate, copper sulfate lead carbonate, lead nitrate, ferrous sulfate,and zinc sulfate. ... 

Treatment of diarylphthalins, obtained by reduction of diarylphthalides, with sulfuric acid results in rearrangement to yield a mixture of benzo[c]furans and anthrones (34JA1406). When diarylphthalins (441) were reacted with sulfuric acid the benzo[c]furans (442) were isolated. A dimeric benzo[c]furan (443) was obtained when the phthalin (444) was treated with acetic anhydride or phenyl isothiocyanate. 

Iodopropene Iodotoluene, 3- and 4-Isobutylbenzene Isobutyl dichloroacetate Isobutyl phenyl ketone Isobutyl trichloroacetate Isobutyronitrile Isopropyl acetate Isopropylbenzene Isopropyl nitrate Isopropyl trichloroacetate Isothiocyanic acid... 

It is a general rule that imidazoles and benzimidazoles are resistant to Friedel-Crafts reactions. This is not surprising since such basic compounds must be markedly deactivated in the presence of Lewis acids. Imidazolin-2-ones appear to be an exception and apparently possess sufficient activation to react. Reactions between imidazoles and Af-methylfor-manilide and phosphoryl chloride are also unproductive. With 4,5-diphenylimidazole, phenyl isocyanate at 80 °C gives products of both N- and C-substitution, but in boiling nitrobenzene only the latter (86) is formed. 2-Methyl-4-phenylimidazole gives (87) under the same conditions, and 1,3-diphenylimidazolium perchlorate is transformed by potassium t-butoxide into a ylide which reacts at C-2 with phenyl isothiocyanate. Sufficient activation is present in l-methyl-2-phenyl-4-phenylaminoimidazole for it to react by substitution at C-5 with acetic anhydride (71JOC3368). 

The synthesis of thiazolo[4,5-d]pyrimidines has been successfully accomplished by various methods. 4-Amino-5-ethoxycarbonylthiazole derivative has been cyclized to thiazolo[4,5-d]pyrimidine by its reaction with phenyl isothiocyanate [87], Many 4-amino-5-carbamoylthiazole derivatives have been cyclized to the corresponding thiazolo[4,5-d]pyrimidines using triethyl orthoformate/acetic anhydride mixture [88-91], Moreover, 4-amino-5-cyano thiazoles have been used to prepare the same fused ring system via their reaction with triethyl orthoformate, followed by treatment of the intermediate with hydrogen sulfide, guanidine, amines, and isothiocyanates [92, 93], Other thiazolo[4,5-d]pyrimidines have been obtained from 4-amino-5-cyano, carbamoyl, or ethoxycarbonyl thiazoles via cyclization with acetic anhydride [94] or formic acid [95],... 

Chloro-3,4-dihydronaphthalene-2-yl)methylene]amino -1 -phenyl-2-thioxo-1,6- dihydro[l,3]thiazolo[5,4-d]pyrimidin-7(2H)-one, which considered as a 7-thia analogue of the natural purine bases, adenine and guanine, was prepared in an excellent yield by condensing 189 with cyanoacetic acid hydrazide followed by Gewald reaction, by reaction of 190 with suhar and phenyl isothiocyanate in the presence of triethylamine as a basic catalyst to give 191(Scheme 84). Thiazolo[5,4-d]pyrimidinone derivative 192 was prepared by heating 191 with a mixture of triethylorthoformate and acetic anhydride (1 1) [117],... 

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