Thionyl halides structures

The propargyl alcohols react with trivalent phosphorus halides to give allenic phosphorus esters as described in Scheme 3 and Table VI. In the case of aryl-substituted alkynols or highly hindered t-propargyl alcohols which contain no free acetylenic —H, thionyl halides or phosphorus trihalides yield bromo- or chloroallenes [74d], Thionyl chloride also reacts in a similar fashion with a wide variety of unhindered secondary alcohols (structure XV) to give a mixture of the chloroallene and chloroalkyne [74a-d]. 

Details of the structures of the pyramidal molecules of thionyl halides (SOX2) and SeOF2 and of the tetrahedral molecules of sulphuryl halides (SO2X2), which have been studied as gases, are included in Tables 16.3 and 16.4. The structures of SeOCl2 (and also SeOF2) have been determined in a number of adducts (p. 600). 

The thionyl and selenyl halides are stable in a vacuum at ordinary temperatures and below, but when strongly heated they decompose, usually to a mixture of products including the dioxide, free halogen, and lower halides. The structures are pyramidal (Fig. 15-13), the S and Se atoms using sets of, roughly, sp3 hybrid orbitals, one of which holds the unshared pair. The S—O bonds in the thionyl halides are evidently resonance hybrids of the canonical structures (15-XIIa, b, c). In b and c the multiple bonding results s—6 s=o <— - s=o... 

The suifuryi halides are known to have distorted tetrahedral structures with S—O bonds similar to those in the thionyl halides. 

The thionyl halides range from 1308 cm for thionyl fluoride, through 1233 for thionyl chloride [52] to 1121 cm for the bromide [85]. Nitrogen substitution also raises s=o as there is no resonance. Sulphinamides have been studied by Smith and Wu [86], by Keat et al. [87] and by Steudel [84]. With A -alkyl groups on both sides of the sulphur atom the frequency is close to 1120 cm", but lower values are found for structures such as R—NHSO—R (1060—1037 cm" ) [86]. In these the bands are usually doubled which may indicate dimerisation as in the amides. Two sulphur atoms attached to the S=0 group give frequencies close to 1105 cm-i. 

A variety of complexes of the thionyl imide anion [NSO] with both early and late transition-metal complexes have been prepared and structurally characterized. Since both ionic and covalent derivatives of this anion are readily prepared, e.g., K[NSO], McsMNSO (M = Si, Sn) or Hg(NSO)2, metathetical reactions of these reagents with transition-metal halide complexes represent the most general synthetic method for the preparation of these complexes (Eq. 7.10 and 7.11). ... 

The phenothiazine duoperone (5) combines structural elements found in phenothiazine and buty-rophenone antipsychotic agents. Alkylation of substituted piperidine 1 with 3-chloropropanol affords the intermediate 2 treatment of this with thionyl chloride converts the terminal hydroxyl to chloride. Alkylation of the phenothiazine 4 with halide 3 affords the antipsychotic agent duoperone (5) [1]. 

Another general method for converting alcohols to halides involves reactions with halides of certain nonmetallic elements. Thionyl chloride, phosphorus trichloride, and phosphorus tribromide are the most common examples of this group of reagents. These reagents are suitable for alcohols that are neither acid sensitive nor prone to structural rearrangement. The reaction of alcohols with thionyl chloride initially results in the formation of a chlorosulfite ester. There are two mechanisms by which the chlorosulfite can be converted to a chloride. In aprotic nucleophilic solvents, such as dioxane, solvent participation can lead to overall retention of configuration.7... 

The parent halides [A X ] (X = Cl, Br) have structure (59), with square planar gold(III).464,465 They can be prepared by direct combination of the elements, and [Au2Cl6] can also be prepared by reaction of H[AuCl4]-3H20 with thionyl chloride.466-468... 

The thionyl and selenyl halides can function as weak Lewis bases, using lone pairs on oxygen and also, more surprisingly, as weak Lewis acids, using vacant d orbitals. The structure of the compound SeOCl2 2py is shown in Fig. 15-13(b). 

The reaction of substituted carboxylic acid amides with a variety of halogenating agents, such as phosphorus pentachloride, phosphorus penta-bromide, thionyl chloride, and carbonyl chloride, produces imidoyl halides or iminium halides, depending upon the structure of the amide. For example, a monosubstituted carboxylic acid amide can react with carbonyl chloride to produce the imidoyl chloride I, or its hydrochloride II, if R is aliphatic. 

Arsenic (III) fluoride solvates anions, such as fluoride ions to give [AsF4] as well as some covalent compoundsi " with the exception of alkali metal fluorides. The AsF4 -ion is isoelectronic with selenium(IV) fluoride, which has a distorted trigonal bipyramidal structure. Ionic compounds are usually insoluble. Various other halides are fluorinated such as phosphorus(III) chloride, phosphorus(V) chloridp, silicon(IV) chloride, thionyl chloride or tungsten hexachloride. Neutralization type reactions, such as... 

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