Disulfur monoxide

K. K. Pandey, Coordination Chemistry of Thionitr osyl, Thiazate, Disulfidothionitrute, Sulfur Monoxide and Disulfur Monoxide, Prog. Inorg. Chem., 40, 445 (1992). 

Within the sulfur sub-group, there are two main types of oxides, the dioxides X 02 (X = S, Se, Te, Po) and the trioxides X Os (X = S, Se, Te). In addition, sulfur also forms disulfur monoxide, S2O. Transient XO species are known in the gaseous phase for S, Se, and Te. Polonium forms a black monoxide PoO. 

A number of suboxides of sulfur have been reported, but in general their composition has not been clearly established. Polysulfur oxides of formula Ss- 10O2 are formed by reaction of hydrogen sulfide and sulfur dioxide. Also, when sulfur is burned with oxygen in very limited supply disulfur monoxide, S20 is formed. This has the structnie... 

Disulfur monoxide, S20, can be prepared, along with SO, by the reduction of S02 in a glow discharge or from the reaction of metal sulfides with SOCl2. In the vapour phase at low pressure it slowly decomposes to S and S02 but in condensed phases it polymerizes. Its structure is similar to that of S02 with an SSO bond angle of 1 180.39 43 The complex t(Ph2PCH2CH2PPh2)2Ir(S20)]Cl (9) has been prepared by the reaction shown in equation (l).41 The complex (9) is air stable and the IR spectrum shows only one v(S—O) at 1043 cm-1.41,44 The complex [Mo(S20)(S2CNEt2)2] has also been isolated in small yield.45... 

The coordination chemistry of NS (thionitrosyl), thiazate (NSO ), disulfidothionitrate (SsN"), sulfur monoxide (SO), disulfur monoxide (S2O), SO2, DMSO, thiosulfate, sulfite, and thiourea ligands is extensive. " Scheme 23 illustrates their coordination modes and some of the complexes that can be generated. 

A slight variation of the [3-I-2] cycloaddition approach <1977ICA(25)165> has also been employed for the diastereoselective synthesis of the corresponding anti- and ry -iron-substituted 1,2-dithiolane 1-oxides 243 from 237, as a source of electrophilic disulfur monoxide, and 7] -allyl iron complex 242 (Scheme 39). The method was also tested with cyclopentadienyl iron dicarbonyl crotonyl complex 244 when four diastereomers 245-248 were generated in modest yields (35%) <19980M5534>. 

Sulfur Monoxide Disulfur Monoxide Disulfur Dioxide Polysulfur Oxides... 

The mixture of gases containing disulfur monoxide from the pyrolysis of thiirane oxide passed for 7 hrs. through a soln. of 2,3-di-2-naphthylbutadiene in toluene... 

Thiophene 1-oxides can also react with sulfur compounds through Diels-Alder reactions to afford the corresponding sulfur-containing cycloaddition products. For example, disulfur monoxide (S2O) can undergo a yn-Jt-face-selective Diels-Alder reaction with 3,4-di-tert-butylthiophene 1-oxide, leading to the sulfur-containing product 47 (Scheme 43) [47, 48]. 

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