Sodium 1-propanethiolate

The second synthetic approach to oidiolactone C (61) is summarized in Scheme 20. This route also commences with the ozonolysis of trans-communic acid 180. Now, when this compound was exposed to ozone in excess, keto aldehyde 187 was obtained in 76% yield. The key step in this approach was the y-lactone closure via chemoselective reduction of the lactone moiety on compound 189 through a SN2 mechanism. Compound 189 could be prepared by saponification of the corresponding methyl ester with sodium propanethiolate. Once the primary alcohol is oxidized, the completion of the synthesis of key lactone 103 only requires the allylic oxidation of the C-17 methyl with concomitant closure of the 8-lactone. This conversion was achieved with Se02 in refluxing acetic acid to give 103 in 51% yield. 

However, there are experiments which show that the anti mode can also take place. For instance, changing piperidine for sodium propanethiolate, the trans and cis mesitoates 1 and 93 (R,=CgH2(CH3)2 gave a mixture of syn and anti Sl products (30). Also, Oritani and Overton (34) showed that the reaction of dichlorobenzoates 98 (R=CH3 or C5H11, and X Cl2CeH3CO2 ) with (S)-a-methylbenzylamine gave a mixture of syn and anti 5N2 products (ratio =6 4). 

Dittmer and Christy64 studied the reactions of thiete sulphone. Included in these was an attempt to synthesize thiete itself, a highly strained olefin of theoretical interest, by the LAH reduction of thiete sulphone. The reduction was expected to be feasible since Bordwell and McKellin63 had found that thietane sulphone was readily reduced, but the only product that Dittmer and Christy isolated was 1-propanethiol (equation 23). Reduction of the thiete sulphone with sodium borohydride in basic aqueous methanol gave a 61% yield of the saturated ring, thietane sulphone. 

Reaction of dichlorobenzaldazine (49) with sodium azide and 1-propanethiol gives the unprecedented ylide 50, as the main product, confirmed by X-ray analysis <00JA2087>. 

Other methods that use 55 anions as precursor for the synthesis of fullerene-derivatives usually involve chemical formation of the anion. Alkylation of 55 has been accomplished, e.g. by reduction with propanethiol and potassium carbonate in DMF [91,92], sodium methanethiolate in acetonitrile [93], the naphthalene radical anion in benzonitrile[94], potassium naphthalide [95] or simply with zinc [96]. 

Aliphatic and aromatic thiols react with pyridine 1-oxides and their quaternary derivatives by Type A, B and/or C pathways, but no such reactions have been reported for pyridine or its salts. 1-Ethoxypyridinium ethosulfate reacts with sodium n-propanethiolate to give mainly pyridine (Type A), and a 6 1 mixture of 3- and 4-pyridyl propyl sulfides (equation... 

Contact of the solid oxidant with organic thiols or sulfides may cause a violent reaction and flash fire [1]. This procedure was recommended formerly for treating spills of sulfur compounds [2,3], but is now withdrawn as potentially hazardous. Use of an aqueous solution of up to 15% concentration, or of 5% sodium hypochlorite solution is recommended [1], Addition of 10 g of oxidant to 5 ml portions of 1-propanethiol or isobutanethiol led to explosions [4]. Application of factorial design techniques to experimental planning gave specific conditions for the safe oxidation of organic sulfides to sulfoxides using calcium hypochlorite or sodium chlorate [5]. 

A new method for the demethylation of codeine to morphine, previously a capricious reaction, has been reported, the product being obtained in good yield. Demethylation by boron tribromide in chloroform gives 90—91%150 and by potassium t-butoxide in propanethiol gives 80% morphine.151 A patent describes an improved method for the preparation of codeinone from thebaine, by adding the alkaloid to anhydrous hydrogen bromide in solution in methylene chloride and dibutyl ether at -20 °C, in the presence of small quantities of iodine, followed by hydrolysis with aqueous sodium bicarbonate. The claimed yields of codeinone are 95% crude and 90% after purification.152 Codeinohe is an intermediate in the conversion of thebaine into codeine. An overall yield of 85% of codeine from thebaine, without purification of any of the intermediates, has been claimed for an... 

The bulk material may ignite or explode in storage. Traces of water may initiate the reaction. A rapid exothermic decomposition above 175°C releases oxygen and chlorine. Moderately explosive in its solid form when heated. Explosive reaction with acetic acid + potassium cyanide, amines, ammonium chloride, carbon or charcoal + heat, carbon tetrachloride + heat, N,N-dichloromethyl-amine + heat, ethanol, methanol, iron oxide, rust, 1-propanethiol, isobutanethiol, turpentine. Potentially explosive reaction with sodium hydrogen sulfate + starch + sodium carbonate. Reaction with acetylene or nitrogenous bases forms explosive products. 

Several thiols occur naturally for example, skunk secretion contains 3-methyll-butanethiol and cut onions evolve 1-propanethiol, and the thiol group of the natural amino acid cysteine plays a vital role in the biochemistry of proteins and enzymes (see Introduction, p. 2). Primary and secondary thiols may be prepared from alkyl halides (RX) by reaction with excess sodium thiolate (SN2 nucleophilic substitution by HST) or via the Grignard reagent and reaction with sulfur. Tertiary thiols can be obtained in good yields by addition of hydrogen sulfide to a suitable alkene. Thiols can also be prepared by reduction of sulfonyl chlorides (Scheme l).la,2a... 

To a solution of dibromomethylbismuthine (3.84 g, 10 mmol) in absolute methanol was added dropwise a solution of sodium methoxide (prepared from sodium 0.46 g, 20 mmol in methanol), and the resulting mixture was warmed gradually to 50°C. The precipitated sodium bromide was filtered off and a methanol solution of an appropriate thiol (20 mmol) was added dropwise to the filtrate at room temperature. The volatiles were removed off in vacuo and the residue was cooled to precipitate a yellow solid, which was filtered and recrystallized from ethanol. The yields of methylbismuth dithiolate from 2-propanethiol, 2-methyl-2-propanethiol, cyclohex-anethiol and 4-methylbenzenethiol were in the range 57-75% [78ZAAC(439)139]. 

In a similar approach, (3,6-diphenyl-l,2,4,5-tetrazin-l-ium-l-yl)(propyl)amide 43 was obtained in a one-pot reaction by treatment of Y -(chloro(phenyl)methylene)benzohydrazonoyl chloride 39 with 1 equiv of sodium azide under phase-transfer conditions, followed by addition of 1 equiv of 1-propanethiol and triethylamine (Scheme 9) <2000JA2087>. 

See Sodium mercaptopropane sulfonate 3-Mercaptopropyltriethoxysilane CAS 14814-09-6 EINECS/ELINCS 238-883-1 Synonyms (y-Mercaptopropyl) triethoxysilane 1-Propanethiol, 3-(triethoxysilyl)- Silane, (3-mercaptopropyl) triethoxy- Triethoxy (3-... 

This method, using ethanethiolate, has been extended to esters. The cleavage of methyl esters by lithium propanethiolate in HMPA, an 8 2 reaction, has been reported. The lithium salt reacts very much faster than the sodium salt. The benzenethiolate and propanethiolate anions have... 

---