Thiocyanate preparation

Gross and Oriez125 reported the synthesis of 4-S-acetyl-6-deoxy-4-thio-D-altrose (302) and 4-S-acetyl-6-deoxy-4-thio-D-idose (303) by using, as starting materials, the corresponding thiocyanates prepared in 35% yield from the 4-O-mesyl derivatives 298 and 299 by Sn2 displacement with thio-... 

Guanidine thiocyanate, prepared by passing ammonia into molten ammonium thiocyanate, is converted into the sulfate. The latter can be converted to the nitrate by the action of calcium nitrate. Gluud, Keller and Schultze, Ber. ges. Kohlentech. 4, 21 (1931) [C. A. 26, 2017 (1932)]. 

The iminothiazocines (53) were prepared via addition of aromatic amines to 5-bromopentane thiocyanate (prepared in turn from 1,5-dibromopentane via formation of the monophthalimide derivative) the initial adduct undergoes intramolecular alkylation to afford the cyclized products in 85-100% yield (Scheme 17) <7lCJC97l>. 

Diethylcyanophosphonate, (Et0)2P(0)CN, is an effective reagent for cyanation and thiocyanate preparation (12.330-12.332). Other uses include olefin epoxidation and peptide bond formation. 

Cupric thiocyanate, prepared in advance, or a paste of copper sulfate and sodium thiocyanate in equivalent proportions is added to a solution of the compound in methanol or acetic acid, and the mixture is warmed to 35-80° until the black cupric thiocyanate has changed completely to the white cuprous thiocyanate. The product is isolated by dilution with... 

When the potassium cyanate used in the above preparation is replaced by potassium thiocyanate (or sulphocyanide), the ammonium thiocyanate formed undergoes partial rearrangement to thiourea (or sulpho-urea). Even above... 

Pheiiyl iso-thiocyanate may be prepared in quantity directly from aniline. Aniline, carbon disulphide and concentrated aqueous ammonia react to form the sparingly soluble ammonium phenyldithiocarbamate this is decomposed by lead nitrate to produce phenyl iso-thiocyanate ... 

Probably first obtained by Hantzsch and Arapides (105) by condensation of a,/3-dichlorether with barium thiocyanate, and identified by its pyridine-like odor, thiazole was first prepared in 1889 by G. Popp (104) with a yield of 10% by the reduction in boiling ethanol of thiazol-2-yldiazonium sulfate resulting from the diazotization of 2-aminothiazole. prepared the year before by Traumann (103). The unique cyclization reaction affording directly the thiazole molecule was described in 1914 by Gabriel and Bachstez (106). They applied the method of cyclization, developed by Gabriel (107, 108), to the diethylacetal of 2-formylamino-ethanal and obtained thiazole with a yield of 62% - Thiazole was also formed in the course of a study on the ease of decarboxylation of the three possible monocarboxylic acids derived from it (109). On the other... 

The reaction is carried out at low temperature in aqueous medium and then allowed to stand overnight (221). Ammonium thiocarbamate is prepared from a cold saturated solution of ammonium thiocyanate, which is gradually added to dilute sulfuric acid at 25°C. The liberated carbonyl sulfide is passed into a saturated solution of alcoholic ammonia at about 10°C (221). The fairly low yield indicates that the reaction has not been greatly developed. 

Hydroxy-4-methylthiazole has been prepared in 68% yield through the reaction of barium thiocyanate with chloroacetone (70). 

Compounds of type 184 were prepared similarly with R, = methyl and R2 = alkanoic esters (136, 229, 304) or carboxyethyl (4, 10, 13, 22, 220) (Table 11-27). Dichloroacetone reacts with ammonium thiocyanate, but... 

Thousands of compounds of the actinide elements have been prepared, and the properties of some of the important binary compounds are summarized in Table 8 (13,17,18,22). The binary compounds with carbon, boron, nitrogen, siUcon, and sulfur are not included these are of interest, however, because of their stabiUty at high temperatures. A large number of ternary compounds, including numerous oxyhaUdes, and more compHcated compounds have been synthesized and characterized. These include many intermediate (nonstoichiometric) oxides, and besides the nitrates, sulfates, peroxides, and carbonates, compounds such as phosphates, arsenates, cyanides, cyanates, thiocyanates, selenocyanates, sulfites, selenates, selenites, teUurates, tellurites, selenides, and teUurides. 

Guanidine salts can be prepared by reaction of thiocyanates and sulfamates (22). 

Uses. There may be some captive use of carbonyl sulfide for production of certain thiocarbamate herbicides (qv). One patent (38) describes the reaction of diethylamine with carbonyl sulfide to form a thiocarbamate salt which is then alkylated with 4-chloroben2yl haUde to produce 3 -(4-chloroben2yl) A[,A/-diethylthiocarbamate [28249-77-6] ie, benthiocarb [28249-77-6]. Carbonyl sulfide is also reported to be useful for the preparation of abphatic polyureas. In these preparations, potassium thiocyanate and sulfuric acid are used to first generate carbonyl sulfide, COS, which then reacts with a diamine ... 

A number of compounds of the types RBiY2 or R2BiY, where Y is an anionic group other than halogen, have been prepared by the reaction of a dihalo- or halobismuthine with a lithium, sodium, potassium, ammonium, silver, or lead alkoxide (120,121), amide (122,123), a2ide (124,125), carboxylate (121,126), cyanide (125,127), dithiocarbamate (128,129), mercaptide (130,131), nitrate (108), phenoxide (120), selenocyanate (125), silanolate (132), thiocyanate (125,127), or xanthate (133). Dialkyl- and diaryUialobismuthines can also be readily converted to secondary bismuthides by treatment with an alkali metal (50,105,134) ... 

Cadmium Hydroxide. Cd(OH)2 [21041-95-2] is best prepared by addition of cadmium nitrate solution to a boiling solution of sodium or potassium hydroxide. The crystals adopt the layered stmcture of Cdl2 there is contact between hydroxide ions of adjacent layers. Cd(OH)2 can be dehydrated to the oxide by gende heating to 200°C it absorbs CO2 from the air forming the basic carbonate. It is soluble ia dilute acids and solutions of ammonium ions, ferric chloride, alkah haUdes, cyanides, and thiocyanates forming complex ions. 

A simple test for ether peroxides is to add lOmL of the ether to a stoppered cylinder containing ImL of freshly prepared 10% solution of potassium iodide containing a drop of starch indicator. No colour should develop during one minute if free from peroxides. Alternatively, a 1% solution of ferrous ammonium sulfate, O.IM in sulfuric acid and O.OIM in potassium thiocyanate should not increase appreciably in red colour when shaken with two volumes of the ether. 

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