Potassium isothiocyanate

This method was extensively reviewed in <84CHEC-I(4)545> and a brief summary is presented here interestingly, since the mid-1980s, this reaction has become less popular. A(-Aryl benzhydrazonyl chlorides react with thiobenzamides to form trisubstituted thiadiazolines which on treatment with alcohols furnish the 2-alkoxy derivative (Scheme 25). A-Arylbenzhydrazonyl chlorides also react with thioketenes to yield 5-methylene thiadiazolines (Equation (16)). Other examples involve the addition of the nitrileimine generated from A-trifluoroacetobenzhydrazonyl bromide to the 0=S of potassium isothiocyanate and methyl isocyanate <87JHC1391>. 

A representative 1,3-dipolar cycloaddition process occurs with yV-aryl-C-(trifiuoromethyl)-nitrilimines, generated from the corresponding hydrazonoyl bromides, c.g. 4. under basic conditions. which can react with dimethyl fumarate and maleate,bicyclic olefins. and dipolarophiles containing cumulative double bonds. With sodium isocyanates as the dipolarophilc the cycloaddition reaction occurs across the C = N bond, while with potassium isothiocyanate it occurs through the C = S bond. ... 

A mixture of hydrazonoyl bromide 4 (2,70 g, 10.1 mmol) and potassium isothiocyanate (3.90 g. 40.2 mmol) in McOH (40 ml.) was refluxed for 3 h. After evaporation of MeOH, the mixture was extracted with toluene and the solvent was removed. The resulting oily matter was placed on a column (silica gel) and eluted with hexanc/EtOAc (3 1) to give compound 5 which was further purified by distillations yield ... 

SYNS ARTEROCYN ATEROCYN KYONATE POTASSIUM ISOTHIOCYANATE POTASSIUM RHODANATE POTASSIUM RHODANIDE POTASSIUM SULFOCYANATE POTASSIUM THIOCYANIDE RODANCA RHODANIDE... 

POTASSIUM (HYDROXYDE de) (FRENCH) see PLJSOO POTASSIUM HYPERCHLORIDE see PLOSOO POTASSIUM HYPOCHLORITE see PLKOOO POTASSIUM lODATE see PLK2S0 POTASSIUM IODIDE see PLKSOO POTASSIUM lODOHYDRARGYRATE see NCPSOO POTASSIUM ISOCYANATE see PLC2S0 POTASSIUM ISOTHIOCYANATE see PLV7S0... 

In possibly the first synthesis of an imidazothiazine, treatment of (703) with potassium isothiocyanate afforded (704), which upon heating in pyridine cyclized to 6-amino-2-bromo-l,5-dihydroimidazo[4,5-e][1.3]thiazine (705) (34JIC867). 

Thioxo-l,3-benzothiazin-4(3/f)-one (250) is formed by reacting 2-thiobenzoic acid (251) with potassium isothiocyanate alkylation of (250) with methyl iodide and sodium hydroxide yields the S-methyl derivative (252) (Scheme 47) <89Ml 607-oi>. 

Compound 190 (R = PhNH) was also obtained by treatment of the corresponding anthranilic acid derivative 189 with hydrogen chloride in ether (2.25 h), with potassium isothiocyanate in aqueous alcohol (20°C, 12 h), and treatment of the reaction mixture at 110-112°C for 1.5 h [114],... 

Potassium tetroxalate. See Potassium tetraoxalate Potassium thiocyanate CAS 333-20-0 EINECS/ELINCS 206-370-1 Synonyms Potassium isothiocyanate Potassium rhodanate Potassium rhodanide Potassium sulfocyanate Potassium thiocyanide... 

Fig. 24. Structure of the (l )crown-6 complex with potassium isothiocyanate. The anion is not shown...

Fig. 38. Structure of the exclusive [2.2.1] complex with potassium isothiocyanate...

Fig. 50. Polymeric structure of the complex between polyether 16 and potassium isothiocyanate. Hydrogen atoms have been omitted for clarity. "W indicates a water molecule. Continuation of adjacent molecules indicated by arrows...

Scheme 4.15 Reaction of 3-(a-chlorobenzyl)quinoxalin-2(l//)-one with potassium isothiocyanate...

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