Benzyl mercaptane

It is important not to allow the reaction mixture to become appreciably alkaline, since the free base then decomposes rapidly yielding benzyl mercaptan, which has an unpleasant odour. 

Dissolve (or suspend) 0-25 g. of the acid in 5 ml. of warm water, add a drop or two of phenolphthalein indicator and neutralise carefully with ca. N sodium hydroxide solution. Then add 2-3 drops of ca. O lN hydrochloric acid to ensure that the solution is almost neutral (pale pink colour). (Under alkaline conditions the reagent tends to decompose to produce the evil-smelling benzyl mercaptan.) If the sodium salt is available, dissolve 0-25 g. in 5 ml. of water, and add 2 drops of ca. 0 -hydrochloric acid. Introduce a solution of 1 g. of S-benzyl-iso-thiuro-nium chloride in 5 ml. of water, and cool in ice until precipitation is Dibasic and tribasic acids will require 0-01 and 0-015 mol respectively. 

The striking effect of the catalyst is exemplified by the reaction of pregna-4, 16-diene-3,20-dione (10) with benzyl mercaptan. In the presence of piperidine only conjugate addition occurs to give (11) whereas with pyridine hydrochloride only the 3-benzyl thioenol ether (12) is formed. In the presence of p-toluenesulphonic acid both reactions take place to yield (13). 

The A" -3-keto group can be selectively protected as a thioenol ether in the presence of a 17- or 20-ketone. High yields are obtained with benzyl mercaptan and pyridine hydrochloride as a 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). 

Reaction of 2-chloromethyl-4//-pyrido[l,2-u]pyrimidine-4-one 162 with various nitronate anions (4 equiv) under phase-transfer conditions with BU4NOH in H2O and CH2CI2 under photo-stimulation gave 2-ethylenic derivatives 164 (01H(55)535). These alkenes 164 were formed by single electron transfer C-alkylation and base-promoted HNO2 elimination from 163. When the ethylenic derivative 164 (R = R ) was unsymmetrical, only the E isomer was isolated. Compound 162 was treated with S-nucleophiles (sodium salt of benzyl mercaptan and benzenesulfinic acid) and the lithium salt of 4-hydroxycoumarin to give compounds 165-167, respectively. 

Steam side was promoted with Benzyl Mercaptan. 

Treatment of aziridine-2-carboxylic ester 251 (Scheme 3.93) with benzyl mercaptan in the presence of boron trifluoride etherate afforded 252 in 71% yield [142]. Compound 252 has been transformed into peptide 253, an analogue of a penicillin precursor. 

C11H5NO2 1631-26-1) see Trovafloxacin mesilate benzylmalonic acid (C]i)H,o04 616-75-1) see Acetorphan benzyl mercaptan... 

Using this procedure, the S-labeled rhena-/8-ketoimine derivatives of benzyl mercaptan, ethanethiol, Me3COC(O)NH0H2CH2SH, iV-acetyl-L-cysteine, and iV-acetyl-D,L-penicillamine have been prepared. 

Peptides typically are prepared for this ligation process using a-alkyl thioesters, because they are simple to make at the time of peptide synthesis. However, due to the relatively slow reaction kinetics of alkyl thioesters, most native chemical ligation processes have been catalyzed through the use of thiol compound additives, such as benzyl mercaptan or thiophenol (Dawson et al., 1997). These compounds react with the initial a-alkyl thioester to form another intermediate, an aryl thioester, which is more reactive toward the N-terminal cysteine on the other peptide to be coupled. A study... 

Despite the many simple methods for preparation of carboxylic esters and thioesters, in some instances, use of 1-acylbenzotriazoles 915 as O and S acylating agents may be advantageous. For example, easy to prepare salicylic acid derivative 941 reacts with cyclopentanol under microwave irradiation to give 92% yield of cyclopentyl salicylate in 10 min <2006JOC3364>. In another example, L-phenylalanine derivative 942 reacts with benzyl mercaptan... 

Dinitrophenyl benzyl sulfide has been prepared by the reaction of benzyl chloride with 2,4-dinitrothiophenol2 or bis-(2,4-dinitrophenyl) disulfide2 and by the condensation of 2,4-dinitrochlorobenzene with benzyl mercaptan.4... 

Benzyl isocyanide, 41, 14 Benzyl mercaptan for synthesis of 2,4-dinitrophenyl benzyl sulfide, 44, 48... 

Yang, D.Q., B. Hennequin, and E. Sacher, XPS Demonstration ofn-n interaction between benzyl mercaptan and multiwalled carbon nanotubes and their use in the adhesion ofPt nanoparticles. Chemistry of Materials, 2006.18(21) p. 5033-5038. 

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