Potassium thiolacetate

Attempted selective displacement (96) of the primary tosylate function in 34 with sodium iodide in refluxing 2-butanone led to the 6-deoxy-6-iodo derivative 35 in 32% yield only, while the di-iodo derivative 36 was formed in 45% yield. These results are to be compared with those reported by Owen and Ragg (85) who observed no reaction with either potassium thiolacetate or potassium thiocyanate in the corresponding / -series. 

The behavior towards potassium thiolacetate of a few alditols bearing acetal rings has been studied. On refluxing in acetone for 6 hours, 2,3,4,5-di-0-methylene-l,6-di-0-tosyl-D-mannitol gave36 an 89% yield of the... 

Potassium nitronates, 950 Potassium nitrosodisulfonate, 940-942 Potassium permanganate, 713, 942-952 Potassium peroxymonosulfate. 952 Potassium persulfate, 952-954 silver-catalyzed, 954 Potassium phenoxide, 300 Potassium-sodium tartrate, 36 Potassium thiocyanate, 199, 378, 954 Potassium thiolacetate, 356,955-956 Potassium triacetylosmate, 955 Potassium triphenylmethide, see Triphenyl-methyl potassium Prednisolone, 997 21-acetate, 604... 

Chapman and Owetf recommend reaction of primary tosylates with potassium thiolacetate as a useful method for the preparation of thiolacetates and thence, by hydrolysis, of thiols. Tetrahydrofurfuryl tosylate on reaction with the reagent... 

The reaction of potassium thiolacetate with the substituted 2-amino-2-deoxy-D-glucose (248) gave a mixture of the 2-amino-2-deoxy-D-alloside... 

Nucleophilic substitution of the halo sugars occurs with such strong nucleophiles as potassium hydrogen sulfide, potassium hydrogen sele-nide, sodium thiosulfate, potassium thiolacetate, potassium methane-thioxide, and sodium azide. If internal attack is not possible, and in favorable cases, substitution occurs with such weaker nucleophiles as ammonia, hydrazine, nitrate ion, and fluoride ion. ... 

The endo-methylsulfonyloxy groups of l,4 3,6-dianhydro-2,5-di-0-(methylsulfonyl)-D-mannitol (18, R = R = OMs) are readily displaced by sodium benzoate in N,N-dimethylformamide to give an L-iditol derivative,280 and by potassium thiolacetate in ethanol307 at 115°. As suggested by Cope and Shen,300 the thiolacetate formed very probably has L-ido stereochemistry (20, R = R = SAc), and is not the D-manno isomer originally proposed. 

Reactivity of Sulfonate Esters with Potassium Thiolacetate ... 

A general procedure for synthesis of terminal episulfides of hexoses or hexitols consists in the action of potassium thiolacetate on an appropriately substituted 5,6-di-O-p-tolylsulfonyl derivative, followed by treatment of the resultant 6-(S-acetyl-6-thio-5-0-p-tolylsulfonyl derivative with cold, methanolic, sodium methoxide the reaction involves rearside attack on C-5 by the sulfur atom at C-6, to displace the p-tolylsulfonyloxy group with inversion.This procedure was used for the synthesis of 5,6-dideoxy-5,6-epithio-l,3 2,4-di-0-ethylidene-L-iditol (82), 5,6-dideoxy-5,6-epithio-l,2 3,4-di-0-isopropylidene-L-guUtol (83), and 5,6-dideoxy-5,6-epithio-1,2-0-isopropylidene-/3-L-idofuranose (84), from 1,3 2,4-di-0-ethylidene-... 

Thio-a-D-xylopyranose (123) was prepared by Adley and Owen in crystalline form by acid hydrolysis of 1,2-0-isopropylidene-5-thio-a-D-xylose (122) the latter was obtained by treatment of 1,2-0-isopropylidene-5-0-p-tolylsulfonyl-a-D-xylose (121) with potassium thiolacetate in boiling JV,lV-dimethylformamide, with subsequent saponification. In a simultane-... 

Displacement of the tosyl function of 120a with potassium thiolacetate in boiling acetone produces (R)-2-acetylthiopropionic acid methyl ester (133) with an optical purity of 92% [45]. Alternately, 133 may be obtained with higher optical purity from an identical reaction with... 

The bis-tosylate 47 is commonly preferred in synthetic sequences over the bis-mesylate 38. Treating 37 with excess j -toluenesulfonyl chloride in pyridine affords excellent yield of (2 S, 3 S)-l,4-bis-tosyl-2,3-0-isopropylidene-L-threitol (47) [24]. Nucleophilic displacement of the tosyl groups with potassium thiolacetate followed by deacetylation provides (2S,3S)-l,4-dithio-2,3-0-isopropylidene-L-threitol (48). 

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