Potassium selenocyanate

The advantage of this method is that it avoids the use of hydrogen selenide, necessary for the preparation of selenourea from cyanamide (14). Benzoylselenourea is synthesized by the method of Douglass (24) by the action of potassium selenocyanate On benzoyl chloride in acetone solution. 

Amino-A.-selenazoline and its 5-methyl derivative have previously been obtained by Baringer (61) starting from 2-bromoethylamine hydrobromide and l-amino-2-bromopropane hydrobromide, respectively, by reaction with potassium selenocyanate. 

A related ring closure is also successful in the thiazole series. Treatment of a /3-amino-a,/3-unsaturated ketone with thiocyanogen gave the intermediate thiocyano compound (323) which underwent ring closure to the 2-iminothiazoline derivative (324) (83MI40300). Related reactions are described in Chapter 4.19, and for those involving potassium selenocyanate see Chapter 4.20. 

Selen-verbindung, /. selenium compound, -wasserstoff, m, hydrogen selenide. -was-serstoffsaure, /. hydroselenic acid, -wismut-glanz, m. guanajuatite. -zelle, /. selenium cell, -zyanid, n. selenium cyanide seleno cyanate. -zyankalium, n. potassium selenocyanate. 

Potassium selenocyanate was obtained from Alfa Inorganics, Inc. 

Starting with 3-aminoselenophene, a thiocyano or a selenocyano group could be introduced in the ortho position using ammonium thiocyanate and potassium selenocyanate.136,137... 

Potassium selenocyanate, 22 73t Potassium silanoate, 22 573 Potassium silicates, 22 451-452 in adhesives and binders, 22 472 manufacture of, 22 464-465 properties of commercial, 22 466t, 468t Potassium-sodium (NaK) alloys, 20 600, 601. See also NaK entries uses for, 20 603-604 Potassium sparing diuretics,... 

Potassium selenocyanate with 2 (or the c-ido isomer) yieldsss l,2-0-isopropylidene-a-D-xy(o-hex-5-enofuranose (65) by elimination of the oxirane oxygen atom. A similar elimination had earlier been... 

Potassium selenocyanate [3425-46-5] M 144.1. Dissolved in acetone, filtered and ppted by adding Et20. 

Cyanogen Triselenide, Se3(CN)2, may be prepared by the action of a current of chlorine diluted with air on an aqueous solution of potassium selenocyanate, KCNSe. It may also be advantageously obtained by the action of nitric oxide on a paste of potassium selenocyanate with water. 

Selenocyanic Acid, HCNSe, may be prepared in solution by decomposing the lead salt (obtained by treating potassium selenocyanate with lead acetate) with hydrogen sulphide.3 It is stable only in neutral or alkaline solution. Selenocyanuric acid has been obtained 4 as a red amorphous powder by the action of cyanuric chloride on sodium selenide and subsequent precipitation by acids. 

Ammonium Selenocyanate, NH4CNSe, may be obtained by double decomposition between potassium selenocyanate and ammonium sulphate and subsequent digestion with alcohol. It is a fairly stable substance, analogous to the sulphur compound. It crystallises in minute needles which are soluble in water with absorption of heat.5... 

Copper Selenocyanate is a brown precipitate obtained by precipitating copper sulphate with potassium selenocyanate. It is rapidly... 

Lead Selenocyanate has been obtained as a lemon-yellow compound by the action of lead acetate on potassium selenocyanate. It is soluble in boiling water but is slightly decomposed. The salt may be exposed without decomposition to a temperature of 100° C., but when moist assumes a pink tint.1... 

Mercurous Selenocyanate, Hg2(CNSe)2, can be obtained as an olive-green precipitate by the action of mercurous nitrate on potassium selenocyanate.3... 

Mercuric Selenocyanate, Hg(CNSe)a, forms a crystalline mass when mercuric acetate is treated with potassium selenocyanate. The crystalline mass consists of white needles which are slightly soluble in cold water but readily soluble in alkali cyanide, thiocyanate and selenocyanate solutions. Mercuric selenocyanate turns brown in air and is decomposed by heat.4... 

Potassium Selenocyanate, KCNSe.—Berzelius prepared this salt by the action of selenium on potassium ferrocyanide 7... 

By fusing pure potassium cyanide with selenium, Muthmann and Schroder obtained potassium selenocyanate satisfactorily.8... 

Iodine reacts with potassium selenocyanate in solution in the presence of much sodium bicarbonate according to the following equation ... 

Silver Selenocyanate, AgCNSe, is obtained as a white precipitate closely resembling silver chloride by the action of silver nitrate on a solution of potassium selenocyanate. If, however, ammonia is previously added in excess to the silver nitrate solution, the selenocyanate is precipitated in minute satin-like crystals. 

Amino-substituted selenophenes are in general unstable compounds, and are conveniently isolated as IV-acetyl or iV-formyl derivatives. An ortho situated electron-attracting substituent such as acetyl, formyl or nitro renders the amino compounds stable. Derivatives of this type can be diazolized and the resulting diazonium salts converted into azides (by reaction with azide ion) (75CR(C)(281)317) and selenocyanates (by reaction with selenocyanide ion) (79BSF(2)237). 3-Acetamidoselenophene can be thiocyanated or selenocyanated in the 2-position by treatment with bromine and potassium thiocyanate or potassium selenocyanate, respectively (78TL1797). 

Phenyl selenides Diphenyl diselenide, 125 Selenocyanates Potassium selenocyanate, 286 Other selenides... 

Selenocyanoacetone, CH3.CO.CH2.SeCN,2 occurs when potassium selenocyanate reacts with chloroacetone in alcohol solution, the solution being evaporated, the residue taken up in water and the aqueous solution extracted with ether. Evaporation away of the solvent gives an oil, which yields an oily hydrazone with phenylhydrazine. 

Selenocyanoacetophenone, CeH5.CO.CH2.SeCN,4 is obtained by treating bromoacetophenone with potassium selenocyanate in alcohol solution. It melts at 85° C. 

The first type of acid to be dealt with contains the selenocyano-grouping —SeCN. This is introduced into aliphatic acids by treating their halogen-substituted derivatives with potassium selenocyanate in the presence of potassium hydroxide, e.g. ... 

---