Stannic chloride compound with

B. Reduction of Dinitrodurene.—A solution of 90 g. of dini-trodurene in 1 1. of glacial acetic acid is boiled in a 12-I. flask (Note 6) 700 g. of stannous chloride is dissolved in 800 cc. of concentrated hydrochloric acid and heated to boiling. The heat is removed from the acetic acid solution of the nitro compound, and the stannous chloride solution is poured very carefully (during about ten minutes) into the dinitrodurene solution. The reaction is complete in fifteen minutes, and as the solution cools the stannic chloride compound of the diamine begins to crystallize. The reaction mixture is cooled to io° in an ice-water bath, and the solid is filtered off by suction, washed twice with 50 cc. of 95 per cent ethyl alcohol and twice with 50 cc. of ether, and dried. The filtrates from the tin compound contain very little of the reduction product and may be discarded. The composition of this compound is [G (CH i)4(NH2-HCI)2l2-SnCl4, and it crystallizes from the reaction mixture in fine, glistening plates which are almost colorless. The yield is 145 g. (97 per cent of the theoretical amount). 

Rose investigated the compounds of ammonia with titanium and stannic chlorides, and with chlorides of sulphur, selenium, phosphorus, arsenic, antimony, aluminium, and iron, as well as the compounds of ammonia with anhydrous halides, sulphates, and nitrates of several metals. He discovered antimony pentachloride by acting on antimony with excess of chlorine, and an interesting compound of it with sulphur chloride, obtained by the action of excess of chlorine on antimony trisulphide. He formulated this as SbCl5,3SCl4, but the pure compound, which can be obtained in crystals, is SbClg, SCI4. ... 

Both aliphatic and aromatic nitro-compounds can be readily reduced in acid solution to the corresponding primary amine. Thus when a mixture of nitrobenzene and tin is treated with hydrochloric acid, the tin dissolves to give stannous chloride, SnCh, which in these circumstances then reacts with more acid to give stannic chloride, SnCl, and the nascent hydrogen produced from... 

Carbonyl Compounds. Cychc ketals and acetals (dioxolanes) are produced from reaction of propylene oxide with ketones and aldehydes, respectively. Suitable catalysts iaclude stannic chloride, quaternary ammonium salts, glycol sulphites, and molybdenum acetyl acetonate or naphthenate (89—91). Lactones come from Ph4Sbl-cataly2ed reaction with ketenes (92). 

Prepa.ra.tlon, Diorganotin dichlorides are the usual precursors for all other diorganotin compounds three primary methods of manufacture are practiced. Dibutyltin dichloride is manufactured by Kocheshkov redistribution from cmde tetrabutyltin and stannic chloride and usually is cataly2ed with a few tenths of a percent aluminum trichloride ... 

The reaction of higher alkyl chlorides with tin metal at 235°C is not practical because of the thermal decomposition which occurs before the products can be removed from the reaction zone. The reaction temperature necessary for the formation of dimethyl tin dichloride can be lowered considerably by the use of certain catalysts. Quaternary ammonium and phosphonium iodides allow the reaction to proceed in good yield at 150—160°C (109). An improvement in the process involves the use of amine—stannic chloride complexes or mixtures of stannic chloride and a quaternary ammonium or phosphonium compound (110). Use of these catalysts is claimed to yield dimethyl tin dichloride containing less than 0.1 wt % trimethyl tin chloride. Catalyzed direct reactions under pressure are used commercially to manufacture dimethyl tin dichloride. 

Most aminothiophenes are prepared by the reduction of nitrothio-phenes. Aminothiophenes or their derivatives have also been obtained through the Hofmann rearrangement of the acid amides, which, however, fails with 2-thenamide, in contrast to the 3-isomer. The Beckmann rearrangement of the oxime of 2-acetylthiophene has been applied successfully to the preparation of 2-acetamidothiophene. The free aminothiophenes are very unstable compounds and it has not been possible to distil 3-aminothiophene. They are best stored as the stannic-chloride double salts and give stable acetyl derivatives. 

Dimethyltin dichloride is used in the glass industry as an alternative to stannic chloride for coating glass with a thin film of stannic oxide 562). The dialkyltin compound vapor is brought into contact with the glass surface at temperatures of 500-600°C, where decomposition and oxidation occurs. 

The scope of the acid-catalyzed formation of C-glycosyl compounds has been greatly expanded with the finding that enol ethers and ketene acetals can be used as the carbon source in electrophilic substitution reactions at the anomeric center.126 Treatment of 198 with the trimethylsilyl enol ether derived from cyclohexanone, in the presence of stannic chloride, led to 2-(2,3,5-tri-0-benzoyl-/J-D-ribofuranosyl)cyelohexanone (206), presumably by way of the inter-... 

Another approach to functionalized C-glycosyl compounds consists in the condensation, catalyzed by stannic chloride, of 1-O-acetyl-2,3,5-tri-0-benzoyl-j8-D-ribofuranose (198) with terminal al-kenes.126 153 Treatment of 198 with 1-hexene in the presence of stannic chloride gave a C-D-ribofuranosyl derivative (213) in high... 

Furthermore, the preparation and reactions of 2-methoxythiophene were studied by Sice (70). This compound was obtained by a copper catalysed Williamson synthesis. It was also found that iodothiophene reacted readily with sodium alkoxides, whereas bromothiophene reacted slowly and chlorothiophene did not react at all. Sodium iodide accelerated the reaction of bromothiophene. The ortho, para orienting alkoxy group on carbon atom 2 increased the directive influence of the sulphur atom to the 5 position but competed with it to induce some attack on the 3 position by electrophilic reagents (nitration, acylation). The acylation of 2-methoxythiophene with stannic chloride at low temperatures furnished a mixture of two isomers. The 5-methoxy-2-acetothienone was obtained in higher yield and was identified by its ultraviolet absorption spectrum. 

Alkyl aryl ketones are convenient intermediates for preparing other substituted aromatic and heteroaromatic compounds. Challenger and co-workers " acetylated thieno[2,3-h]thiophene (1) with acetyl chloride and stannic chloride [Eq. (59)]. The 2-acetylthieno[2,3-A]-thiophene obtained by this method was reduced to the 2-ethyl derivative (20) identical with the product of an independent synthesis. ... 

Many chlorides, especially those of the metals, combine with sulphur tetrachloride to produce unstable crystalline additive compounds 2 thus, iodine trichloride, antimony pentachloride, titanium tetrachloride, stannic chloride, ferric chloride, and also arsenic fluoride, yield crystalline products containing the added molecule SC14 this provides strong evidence of the definite existence of this chloride of sulphur. 

Concentrated hydrochloric acid also dissolves the trichloride, about 100 g. of the latter dissolving in 1 litre of acid at 100° C.7 Dissolution in hydriodic acid is accompanied by evolution of heat and the triiodide is formed.8 Ethyl iodide reacts similarly.9 Double decomposition reactions occur w hen arsenic trichloride is heated with phosphorus triiodide, stannic iodide or germanium iodide, the reactions being complete.10 Similarly, potassium iodide heated with arsenic trichloride in a sealed tube at 210° C., and potassium bromide at 180° to 200° C., form respectively arsenic triiodide and tribromide.11 Stannous chloride, added to the solution in hydrochloric acid, causes reduction to arsenic (see p. 29). Arsenic trichloride may be completely separated from germanium chloride by extraction with concentrated hydrochloric acid.12 Ammonium, sodium and cobaltic chlorides react with arsenic trichloride to form additive compounds with magnesium, zinc and chromic chlorides there is no reaction.13... 

The usual routes to 1,3-oxazinium salts consist of 1,4-cycloadditions between either a,/3-unsaturated /3-chlorocarbonyl compounds and nitriles or between N-acylimidoyl chlorides and alkynes. Stannic chloride is an effective catalyst for both reactions (c/. Scheme 62). 1,3-Thiazinium perchlorates are synthesized by reacting oxazinium salts with hydrogen sulfide in absolute acetonitrile and then treating the product amides (185) with perchloric acid (Scheme 69) (72S333). 

Such compounds are unstable unless the double bond is held in conjugation with other systems as, for example, when it is part of an aryl ring. Indeed, dihydro-3,1-benzoxazines are readily accessible from 2-aminobenzyl alcohols by condensation with aldehydes or ketones (Scheme 84) (75AP622). Oxacephems (199) also contain the 3,6-dihydro-2//-l,3-oxazine unit and they are formed for instance, on cyclization of chlorolactams (198) by the action of stannic chloride (B-80MI22701). 

Tin forms dihahdes and tetrahahdes with all of the common halogens. These compounds may be prepared by direct combination of the elements, the tetrahalides being favored. Like the halides of tile lower main group 4 elements, all are essentially covalent. Their hydrolysis requires, therefore, an initial step consisting of the coordinative addition of Iwo molecules of water, followed by the loss of one molecule of HX. the process being repeated until the end product ft S111 Oil c is obtained. The most significant commercial tin halides are stannous chloride, stannic chloride, and stannous fluoride. 

Telraorganotins, RaSn, prepared either by alkylation of tin halides with Grignard Reagents or alkyl lithium by reaction of an organic halide with a tin-sodium alloy by direct reaction of tin with an organic halide or by reaction of stannic chloride with alkyl aluminum compounds. 

In 2-alkyl-substituted thienothiophenes I and 2 the free a-position is attacked.44,57 7,219 However, acetylation of 2-ethylthieno[2,3-61-thiophene (20) produced, together with 2-acetyl-5-ethylthieno[2,3-61-thiophene, small quantities of some other compound which was ascribed219 the structure of 3-acetyl-2-ethylthieno[2,3-61thiophene by analogy with the acetylation products of 2-ethylthiophene.24 Acetylation of 2,5-dialkylthienothiophenes 1 and 2, like 2,5-dialkyl-thiophenes,247 proceeds easily in the presence of stannic chloride. For example 2,5-diethylthieno[2,3-6]thiophene (with AcCl/SnCl/QH ) forms 3-acetyl-2,5-diethylthieno[2,3-6]thiophene in 80% yield. 7... 

Nitrous acid is also employed as a nitrating agent in organic chemistry. Thus, M. F. Aitken and T. H. Reade studied its action on p-iododimethylaniline, and obtained nitro-derivatives J. Reilly and P. J. Drumm, its action on substituted p-phenylenediamines and F. Bettzieche, and R. H. A. Plimmer, its action on amides and other amino-compounds. Nitrogen trioxide was found by H. Reihlen and A, Hake to form att unstable complex with stannic chloride—possibly 38nCl4.4N02. Nitrogen trioxide reacts with stannic chloride not in the ordinary blue but in the colourless form. A. Klemenc and R. Scholler studied the partition of nitrous acid between ether and water. The poisonous qualities of nitrous acid have been discussed by A. Purcell,3 etc. 

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