4,5-Dihydro-2- thiazole

A. 2-Allylthio-2-thiazoline [Thiazole, 4,5-dihydro-2-(2-propenyltliio)-]. A solution of 11.9 g. (0.100 mole) of 2-mercapto-2-thiazoline [2-Thiazoli-dinethione] (Note 1) in 00 ml. of tetrahydrofuran is prepared in a 200-ml., one-necked, round-bottomed flask fitted with a 25-ml.,... 

Thiazole, 4,5-dihydro-2-[[l-(phenylmethyl)-2-propenyl] thio] - [52534-824], 78 Thiazole, 4,5-dihydro-2-[(phenylmethyl)-thio] - [41834-62-2], 82 Thiazole, 4,5-dihydro-2-[(3-phenyl-2-propenyl)thio] - [57620-95-8], 82 Thiazole, 4,5-dihydro-2-(2-propenylthio)-[3571-74-2],77... 

Thiazoline, 2-methylthio- [Thiazole, 4,5-dihydro-2-(methylthio)-j, 82 2-Thiazoline, 2-(4-phenyl-l -bu ten-3-yl)thio-[Thiazole, 4,5-dihydto-2-[ [Mphenyl-methyl)-2-propenylj thio] -], 78 Thiazolium,7V-methyl-2-methylthio-, iodide [Thiazolium, 4,5-dihydro-3-methyl-2-(methylthio)-, iodide], 80 Thioacetic acid, trifluoro-, S-ethyl ester [Ethanethioic acid, trifluoro-,5-ethyl ester], 125 Toluene [Benzene, methyl-], 85 Toluene, p-bromo- [Benzene, l-bromo-4-methyl-], 86... 

Other Condensed Systems incorporating Thiazole. - Dihydro- and tetrahydro-cyclopropa[c ] thiazole derivatives, cyclenothiazoles, hexahydrocyclo-octa[rf] thiazolo [3,2-a] pyrimidines, 2-amino-10,l 1 -dihydrophenanthro-... 

Rhodacyanines possess two chromophoric systems. They are at the same time neutrocyanine derivatives, which involves position 5 of the ketomethylene, and methine cyanine, which involves position 2. Following lUPAC s standard nomenclature rules, structure 7 is named 3-ethyl-4-phenyl-2- 4-oxo-3-ethyl-5-[2-(3-ethy]-2,3-dihydro-benzo-l,3-thiazo-lylidene)ethylidene]-tetrahydro-l,3-thiazolylidene-methyl -1.3-thiazolium iodide (Scheme 5). It implies that the 4-phenyl thiazole ring having the... 

With 7-bromobenzo[a]cyclohept-2-ene-l-one in alcohol solution, the 9,10-dihydro-8H-benzo-4,5-cyclohepta-[d]-thiazol-2-ylhydrazine (143) was obtained in 46% yield (Scheme 69) (679, 688, 689). 

Reactions. Heating an aqueous solution of malonic acid above 70°C results in its decomposition to acetic acid and carbon dioxide. Malonic acid is a useful tool for synthesizing a-unsaturated carboxyUc acids because of its abiUty to undergo decarboxylation and condensation with aldehydes or ketones at the methylene group. Cinnamic acids are formed from the reaction of malonic acid and benzaldehyde derivatives (1). If aUphatic aldehydes are used acryhc acids result (2). Similarly this facile decarboxylation combined with the condensation with an activated double bond yields a-substituted acetic acid derivatives. For example, 4-thiazohdine acetic acids (2) are readily prepared from 2,5-dihydro-l,3-thiazoles (3). A further feature of malonic acid is that it does not form an anhydride when heated with phosphorous pentoxide [1314-56-3] but rather carbon suboxide [504-64-3] [0=C=C=0], a toxic gas that reacts with water to reform malonic acid. 

Thiazole, 2,4,5-trimethyl-thermodynamic data, 6, 245 (66CR(C)(263)1333) Thiazole, 2,2,4-trimethyl-4,5-dihydro- H NMR, 5, 17 (64JCP613)... 

Imidazo[2,l-6]thiazole, 3-aryl-5,6-dihydro-biological activity, 6, 1024 Imidazo[2,l-6]thiazole, 5,6-bis(4-... 

H-Imidazo[4,5-d]thiazole, 4,6-dihydro-2,4,6-triphenyl-synthesis, 6, 990 Imidazothiazoles structure 6 977... 

Thiazoline, 2-ethylthio [Thiazole, 2-(ethylthio)-4,5-dihydro-], 82 2 Thiazohne, 2-mercapto [2 Thiazohdine-thione], 77... 

N,N-Diacyl-thiohydroxylamine werden durch Natrium-bis-[2-methoxy-athyl]-dihydrido-aluminat in Benzol mit guten Ausbeuten zu Aldehyden reduziert. Mit Hilfe von 3-Oxo-2,3-dihydro-(benzo-[d]-l,2-thiazol)-l,l-dioxid gelingt es auf diese Weise Car-bonsaure-chloride auf einfache Weise in Aldehyde zu iiberfiihren z. B.2 ... 

Aldehyde allgemeine ArbeitsvorschrifL Zu einer Suspension von 1 Mol 3-Oxo-2-acyl-2,3-dihydro-(ben-zo-[d]-l,2-thiazol)-l,l-dioxid in abs. Benzol wird unter Riihren und unter Stickstoff cine Losung von 0,5 Mol Natrium-bis-[2-methoxy-athoxy]-dihydrido-aluminat in abs. Benzol bei 0-5° innerhalb 5—10 Min. in kleinen Portionen gegeben. Man riihrt 2 Stdn. bei dieser Temp., vcrsetzt mit Wasser, saugt den Niederschlag ab, wascht mit Benzol nach, schiittelt die waBr. Phase mit Benzol aus, und dampft nach Trocknen die Benzol-Losungen ein. Der Riickstand wird destilliert bzw. kristallisiert. 

Acylthio-4,5-dihydro-l,3-thiazole werden durch Bis-[2-methyl-propyl]-aluminiumhydrid mit guten Aus-beuten zu Aldehyden reduziert1. 

Thiazolidine, 2,5-Dihydro- 1,3-thiazole, Tetrahydro-l,3-thiazine und 5,6-Dihydro- 1,3-thiazine werden durch Lithiumalanat6,7 und meist auch durch Natriumboranat7 zu den (w-Mercapto-aminen aufgespalten. 1,3-Thiazolidine lassen sich mit einem Lithi-umalanat-OberschuB ahnlich den 4,5-Dihydro-1,3-oxathiolanen zu Athylaminen wei-terreduzieren7,8 ... 

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