Thiazolium, 5- -, chloride

Imidazo[ 1,2-e]thiazoles biological activity, 6, 1024 reactions, 6, 1041 synthesis, 6, 1048 Imidazo[2, l-6]thiazoles electrophilic substitution, 6, 979 synthesis, 6, 992, 993, 1010, 1018 Imidazo[3,l-6]thiazoles synthesis, 6, 986 Imidazo[5,l-6]thi azoles biological activity, 6, 1024 synthesis, 6, 1017 Imidazo[2,l-6]thiazolium chloride synthesis, 6, 1013... 

H-Imidazo[2,l-6]thiazolium chloride, 6,7-dihydro-3-(5-nitro-2-furanyl)-biological activity, 6, 1024 5H-Imidazo[2,l-6]thiazolium salts, 6,7-dihydro-synthesis, 6, 992... 

Thiazolium chloride, 3-benzyl-5-(2-hydroxyethyl)-4-methyl-catalyst... 

Substituted tetrazoles reacted with 4,5-dichloro-l, 2,3-thiazolium chloride (Appel salt) to give 1,3,4-thiadiazole oligomers <00TL9407>. 2-Benzyloxymethyl-5-(tributylstannyl)tetrazole (203) was found to be a versatile reagent for the conversion of aryl-and heteroarylhalides to 5-aryl- and 5-heteroaryl-lf/-tetrazoles 204 <00TL2805>. 

In the late 1990s, Tins and co-workers described a formal total synthesis of roseophihn [99, 100], The Stetter reaction was well suited for the coupling of partners 157 and 158 in the presence of 3-benzyl-5-(hydroxyethyl)-4-methyl thiazolium chloride (Scheme 24). 

Two rearrangements may well be regarded as further examples of interconversion between meso-ionic isomers. The 1,3-diazolium chloride (310) and warm dilute aqueous potassium hydroxide yield 4-anilino-l-methyl-2-phenylimidazole (311), presumably via the indicated meso-ionic intermediates. The transformation 312 - 313 by treatment of the thiazolium chloride with warm aniline may be similarly interpreted. ... 

DIKETONES l-Benzyl-4-(2-hydioxy-ethyl)-5-methyl-l, 3-thiazolium chloride. Copper(II) trifluoromethanesulfonate. 

The usual precursor is a cyclic thioamide. On formation, the Wp-chloroethylthiazolidine-2-thione (48) spontaneously ring-closed to the tetrahydrothiazolo[2,3-fc]thiazolium chloride (49) (7ICHE1534). Similar reactions of imidazole analogues of (48) give compounds of type (50). 

The thiazolium salt 3-benzyl-5-(2-hydroxyethyl)-4-methyl-l,3-thiazolium chloride is an excellent catalyst for the addition of unsaturated aliphatic aldehydes to vinylketones (79CB84). The presence of a base such as sodium acetate or triethylamine is required, for the thiazolium salt must first be transformed into the ylide structure (615), which then exerts a catalytic effect resembling that of cyanide ion in the benzoin condensation (Scheme 137). Yields of 1,4-diketones (616) produced in this process were generally good. The use of thiazolium salts for other related reactions has been reviewed (76AG(E)639). 

Benzyl-5-(2-hydroxyethyl)-4-methyl-1,3-thiazolium chloride (4568-71-2), 65, 26 N-Benzylidenebenzenesulfonamide (13909-34-7), 66, 203, 204, 206, 210 Benzylidenemalononitrile Malononitrile, benzylidene- Propanedinitrile, (phenylmethylene)- (2700-22-3), 65, 32 Benzyl mercaptan a-Toluenethiol Benzenemethanethiol (100-53-8), 65, 215 N-BENZYL-N-METHOXYMETHYL-N-(TRIMETHYLSlLYL)METHYLAMINE BENZENEMETHANAMINE, N-(METHOXYMETHYL)-N-[(TRlMETHYL-SILYL)METHYL]- (93102-05-7), 67, 133 1-BENZYLOXY-4-PENTEN-2-OL 4-PENTEN-2-OL. 1 -(PHENYLMETHOXY)- (58931-16-11), 69, 80... 

Various thiamine derivatives were prepared on polymer support and were tested in C-C coupling reactions.40 The most straightforward approach was the alkylation of substituted 1,3-thiazoles with chloromethyl polystyrene resin yielding supported thiazolium chloride salts. Alternatively, resin-supported thiamine derivatives were constructed in a two-step process by alkylation of the primary alcohol with chloromethyl polystyrene followed by alkylation of the ring nitrogen yielding resin 12 (Fig. 8). Not only does this pathway introduce a spacer between the active thiamine... 

A. Z, s-Vndeoanediona. A 1000-mL, three-necked, round-bottomed flask equipped with a mechanical stirrer, short gas inlet tube, and an efficient reflux condenser fitted with a potassium hydroxide drying tube is charged with 26.8 g (0.1 mol) of 3-benzyl-5-(2-hydroxyethyl)-4-methyl-l,3-thiazolium chloride (Note 1), 500 mL of absolute ethanol, 77.2 g (1.1 mol) of 3-buten-2-one (Note 2), 60.6 g (0.6 mol) of triethylamlne (Note 3), and 114.2 g (1.0 mol) of heptanal (Note 4). A slow stream of nitrogen (Note 5) is started and the mixture is stirred and heated in an oil bath at 80°C. After 16 hr the reaction mixture is cooled to room temperature and concentrated by rotary evaporation. Then 500 mL of chloroform is added to the residue and the... 

Benzyl-5-(2-hydroxyethyl)-4-methyl-l, 3-thiazolium chloride is supplied by Fluka AG, Buchs, Switzerland and by Tridom Chemical, Inc., Hauppague, New York. The thiazolium salt may also be prepared as described in Org. Synth. 1984, 42, 170. 

CN . 3-[(4-amino-2-methyl-5-pyrimidinyl)methyl]-4-methyl-5-(4,6,6-trihydroxy-4,6-dioxido-3,5-dioxa-4,6-diphosphahex-1 -yl)thiazolium chloride... 

The reaction of 2-chloroethyl isothiocyanate with ethylene sulfide in the presence of Et4N+Br (20 d, 20 °C) gave an 83% yield of 2,3,5,6-tetrahydrothiazolo[2,3-h]thiazolium chloride (265) by way of intermediate (264) (71CHE1534). The identical ring system is formed on treatment of V,lV-bis(2-chloroethyl)amine and CS2 in aqueous NaOH (63JPR(291)10l). With 2-chloroethyl isothiocyanate and N-phenylethyleneimine, in the absence of a catalyst, imidazo[2,1 -hJthiazolium chloride (266) is obtained in 60% yield. 

Dihydro-3-(5-nitro-2-furanyl)-5//-imidazo[2,l-6]thiazolium chloride (furazolium chloride) is a topical antibacterial agent. Substituted imidazo[l,2-c]thiazole derivatives are antihypertensives, CNS stimulants, and appetite suppressants. 2H- l,3-Dithiolo[4,5-c]pyrazole-5-thiones and imidazo[5,1 -b jthiazoles are fungicidal with low toxicity to plants, animals and hum ns. 

Benzyl-5-(2-hydroxyethyl)-4-methyl-1,3-thiazolium chloride Thiazolium, 3-benzyl-5-(2-hydroxyethyl)-4-methyl-, chloride (8) Thiazolium,... 

Interestingly, the mild reaction conditions of the CIR are fully compatible with the Stetter reaction. As a result a sequence of transition metal, base and organoca-talysis can be easily conceived. Upon CIR of electron-deficient (hetero)aryl halides 11 and (hetero)aryl propargyl alcohols 12, and after subsequent addition of aliphatic or aromatic aldehydes 92 and catalytic amounts of thiazolium salt 93 1,4-diketones 94 are obtained in moderate to excellent yields in a one-pot procedure (Scheme 50) [259, 260]. For aromatic aldehydes the catalyst precursor of choice is 3,4-dimethyl-5-(2-hydroxyethyl) thiazolium iodide (93a) (R = Me), and for aliphatic aldehydes 3-benzyl-4-methyl-5-(2-hydroxyethyl)-thiazolium chloride (93b) (R = CH2Ph) is applied. 

SYNS 3-((4-AMINO-2-METHYL-5-PYRIMIDINYL)-METHYL)-5-(2-HYDROXYETHYL)-4-METHYL-THIAZOLIUM CHLORIDE ANEURINE APATATE DRAPE B-AMIN BEIVON BETABION BETAL-IN S BETAXIN BETHIAMIN BEWON ORYZANIN ORYZANINE THIAMIN THIAMINE MONOCHLORIDE VINOTHIAM VITAMIN B1 VITANEURON... 

In the laboratory of A. Millar, the convergent enantloselective synthesis of CI-981, a potent and tissue-selective Inhibitor of HMG-CoA reductase was achieved. The central tetrasubstituted pyrrole ring was prepared via the Paal-Knorr pyrrole synthesis. The required 1,4-diketone precursor was efficiently prepared by the Stetter reaction between p-fluorobenzaldehyde and an unsaturated amide. Interestingly, the A/-benzyl thiazolium chloride catalyst afforded only the benzoin condensation product and none of the desired diketone. However, when the A/-ethyl thiazolium bromide catalyst was employed, under anhydrous and concentrated reaction conditions, the 1,4-diketone was formed in good yield. The authors also noted that the simple dilution of the reaction mixture resulted in a dramatic increase in the formation of the undesired benzoin condensation product. 

---