Thiophenol 0-carboxylic acid

DBU was also used in the (ert-butyldimethylsilylation of alcohols, phenols, mercaptans, thiophenols, carboxylic acids, amines, and ketones with tcrt-butyldimethylchlorosilene in dichloromethane, benzene, or acetonitrile at room temperature or at 80°C (85TL475). Good chemoselecti vity was observed in the case of alcohol. The formation of primary silyl ethers was the quickest. 

Dilute sodium hydroxide solution. Carboxylic acids (RCOOH), sulphonic acids (RSO3H), phenols (ArOH), thiophenols (ArSH), mer-captans (RSH), imides (RCONHCOR), aryl sulphonamides (AxSOjNHj), arylsulphonyl derivatives of primary amines (AxSOjNHR), oximes (RCH=NOH), primary and secondary nitro compounds (RCH=NOOH and RjC=NOOH-oci forms), and some enols (e.g., of 1 3-diketones... 

Me3SiCH2CH=CH2i TsOH, CH3CN, 70-80°, 1-2 h, 90-95% yield. This silylating reagent is stable to moisture. Allylsilanes can be used to protect alcohols, phenols, and carboxylic acids there is no reaction with thiophenol except when CF3S03H is used as a catalyst. The method is also applicable to the formation of r-butyldimethylsilyl derivatives the silyl ether of cyclohexanol was prepared in 95% yield from allyl-/-butyldi-methylsilane. Iodine, bromine, trimethylsilyl bromide, and trimethylsilyl iodide have also been used as catalysts. Nafion-H has been shown to be an effective catalyst. 

While carboxylate anions do not add to the imonium function of ketone derived enamines, such as morpholinocyclohexene, when these are combined with carboxylic acids (38), the addition of thiophenol or benzyl mercaptan leads to a-aminothioethers (509,510). 

Reactions between aziridine-2-carboxylic acids and thiols in aqueous solution have been explored by Hata and Watanabe [112]. The reactions occurred predominantly at C-2 instead of C-3 to afford 3-amino acids, with the reaction between 148 (Scheme 3.53) and thiophenol in 0.2 m sodium phosphate buffer at room tem-... 

Carboxylic acids such as acetic acid react with alcohols such as methanol or with methoxytrimethylsilane 13 a in the presence of trimethylchlorosilane (TCS) 14 in THF or 2-methyl-THF to give esters such as methyl acetate in 97% yield and hex-amethyldisiloxane 7. Even methyl pivalate can be readily prepared in 91% yield [111]. Reaction of a variety of carboxylic acids, for example N-benzoylglycine 329, with two equivalents of yS-trimethylsilylethanol 330 and with 14 has been shown to afford esters such as 331 in 98% yield [112, 112 a]. Likewise, silylated carboxylic acids react with silylated alcohols or thiophenols in the presence of 4-trifluoro-methylbenzoic anhydride and TiCl4/AgCl04 to furnish esters or thioesters in high yields [113, 114] (Scheme 4.43). 

Tetramethylhydrazine, see Dimethylamine Tetramethylsuccinonitrile, see Aldicarb Tetrazene, see Naphthalene 2-Thiazolidinethione-4-carboxylic acid, see Captan 1.1 -Thiobis-ethane, see Phorate 3.3 -Thiobis(methylene)-1.2.3-benzotriazin-4(3Afl-one, see Azinnhos-methyl Thiomalic acid, see Malathion Thiomethylbenzazimide, see Azinphos-methyl Thiophene, see Benzene Thiophenol, see Fonofos Thiophosphoric acid, see Phorate Thiram monosulfide, see Thiram o-Tolualdehyde, see oXylene m-Tolualdehyde, see m-Xylene p-Tolualdehyde, see p-Xylene Toluene, see Benzene. 2-ChlorobiDhenyl. 4 Chlorobinhenyl. Isobutylbenzene, Methylcyclohexane, Styrene, p-Xylene... 

Methylene-substituted tetrahydro-l,3-oxazine 141 underwent ring opening in response to nucleophilic attack by carboxylic acids or thiophenols to afford the A -acetyl derivatives of the corresponding 0-acyl-l,3-amino alcohols 168 or aminoalkyl sulfides 169 in high yields (Scheme 27) <2006JC0262>. 

GC analysis of underivatized polar fractions did not reveal any volatile sulfur compounds. However, once these fractions were methylated with diazomethane, a number of sulfur compounds were detected. (Presumably, the diazomethane methylated either carboxylic acid, phenolic, thiophenolic, sulfonic acid or even alcohol or thiol groups and thereby increased their parent molecules volatility). These additional sulfur compounds are currently under investigation in our laboratories and the results of these studies will be reported later. 

THF (13.5 ml) and DMF (1.5 ml) are cooled to -35°C and degased by alternating reduced pressure and nitrogen three times. Thiophenol (0.22 ml, 2.14 mmol) is added followed by potassium butoxide/THF (1.978 M, 0.7 ml, 1.38 mmol). After 5 min, 7-SDMS baccatin III 13-(2R,4S,5R)- and (2S,4S,5R)-2,4-diphenyl-3-(4-nitrobenzenesulfonamido)-l,3-oxazolidine-5-carboxylic acid ester (877 mg, 0.762 mmol) is added. After the solids are added, the reaction mixture is slowly warmed to -10°C. The mixture is stirred at -10°C until the red color fades to yellow. After 3 h the bath is dropped allowing the mixture to warm to 20-25°C. At 20°-25°C the reaction is stirred for 1 h before assaying by TLC and HPLC. Sodium bisulfite (241 mg, 2.31 mmol) is added in water (5 ml). The mixture is stirred at 20°-25°C and after approximately 115 h the reaction is complete (by TLC) giving the free amine 7-SDMS baccatin III 13-(2R,3S)-3-amino-3-phenyl-2-hydroxypropionate. 

In this case, carboxylic acid fragment 12a was prepared from benzoate 14 and amine 15 in 82% overall yield. Likewise, benzothiophene 13 was generated from thiophenol 16 and bromoketone 17 in 55% overall yield. 

Carboxylic acids, protection of, 224-276 as amides and hydrazides, 270-276 as esters, 227-270 Reactivity Chart 6, 433-436 S-Carboxymethyl thioethers, to protect thiophenols, 294-295 Catechols, protection of, 170-174 as cyclic acetals and ketals, 170-172 as cyclic esters, 173-174 Reactivity Chart 4, 425-428 CBZ, see Benzyl carbamates Chloroacetamides, to protect amines, 352-353... 

Pyrrolo[2,l-4 [l,5]benzothiazocine 563a was prepared by alkylation of thiophenol 602 with a-bromophenylacetic acid 603 that furnished the carboxylic acid 604 (73% yield) which, by an intramolecular cyclization in presence of PCl5, yielded 563a (41% yield) (Scheme 121) <1997EJM241>. 

Thermal decomposition of the diacyl peroxide of (/ )-(-I- )-methyl-2,2-diphenylcyclopropane carboxylic acid 11 without or in the presence of a good radical trap, such as iodine or thiophenol [18] (Scheme 2). 

Sodium enolates of ketones and disodium enediolates of substituted phenylacetic acids reacted with activated aziridines to afford 7-amido ketones and 7-amidobutyric acids, respectively (Scheme 72). Aziridine-2-carboxylic acid esters can be utilized as versatile precursors for amino acid derivatives. Although the product distribution resulting from the reaction of activated aziridine-2-carboxylates with amines depends on the structure of the reactants, the reactions with alcohols or thiols in the presence of acidic cabilysts generally gave the a-amino acid derivatives (Scheme 73). ° On the other hand, free 3-methyl-2-aziridinecarboxylic acids (168) reacted with thiophenol, cysteine and glutathione to afford P-amino acid derivatives with sulfur substituents at the a-position as the main product (Scheme 73). ... 

The use of thiophenol in this reaction leads to an insertion product that can be isolated. With more acidic reagents, such as carboxylic acids, the insertion is irreversible, as in reaction (c), giving good yields (R = Cy, 85% Ph, 60%). Insertions into carboxylic functionalities appears to be widely applicable, although relatively few compounds have been reported to date. 

Although this substance is a weaker base than either sodium ethoxide or sodium phenoxide, it has much greater nucleophilic power. Sheehan and Daves- used it in dimethylformamide at or below room temperature to cleave sensitive ester functions (principally phenacyl) at the C—O bond to generate sodium salts of the corresponding carboxylic acids in good to excellent yield, as illustrated for phenacyl benzoate. The reagent is prepared by adding thiophenol to a molar proportion of... 

Thallium triacetate, 406 Thallous carboxylates, 410 Thallous ethoxide, 407-411 Thebaine, 330, 331 Thiacyclohexane, 358 Thiazolidine-4-carboxylic acid, 27 Thiele reaction, 7-9, 12, 13 Thiepin-1,1-dioxide, 392 Thioanisole, 99, 311, 324 Thiocarbonates, 105, 106 N,N -Thiocarbonyldiimidazole, 411-412 Thiocyanogen, 105, 440 Thionyl chloride, 176, 395, 410, 412 Thiophenols, 173, 174 Thiophosgene, 412 Thiourea, 157, 412-413 Thymidine, 297, 298 Thymidine 5 -phosphate, 298 Thymine, 370 Tigonin, 136 Tin, 414... 

I-Indolyl)propanoic acid (73.4a, R = H) forms a third ring by attack of the carboxylic acid group at C-2 of the indole, but a 3-methoxycarbonyl substituent directs the attack to the peri (C-7) position [2997,3015,31 IS]. When the chloro ester (73.6) is heated with either an amine or a thiophenol, a high yield of the... 

In the standard form of this route, a carboxylic acid is heated with the orffto-disubstituted benzene orf/to-amino-phenol, -thiophenol or -aniline. An iminoether will react at a much lower temperature and iminochlorides, generated in situ using the acid, triphenylphosphine and hot carbon tetrachloride, can be used for benzimidazole or benzoxazole synthesis. Orthoesters with a KSF clay is a highly recommended variant and can be used for the synthesis of all three unsubstituted benzo-l,3-azoles. ... 

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