Benzenesulfinic 2,5-dimethyl

Directed lithiation of aromatic compounds is a reaction of broad scope and considerable synthetic utility. The metalation of arenesulfonyl systems was first observed by Gilman and Webb and by Truce and Amos who reported that diphenyl sulfone is easily metalated at an orf/io-position by butyllithium. Subsequently, in 1958, Truce and coworkers discovered that metalation of mesityl phenyl sulfone (110) occurred entirely at an orf/io-methyl group and not at a ring carbon, as expected. Furthermore, refluxing an ether solution of the lithiated species resulted in a novel and unusual variation of the Smiles rearrangement and formation of 2-benzyl-4,6-dimethyl-benzenesulfinic acid (111) in almost quatitative yield (equation 78). Several other o-methyl diaryl sulfones have also been shown to rearrange to o-benzylbenzenesulfinic acids when heated in ether solution with... 

Benzenesulfinic acid, 4-methyl-2,2-dimethyl-propyl ester[13146-08-2], 58, 147 Benzenesulfinic acid, 4-methyl-, potassium salt [19294-29-2],57,8 Benzenesulfinic acid, 4-methyl-, sodium salt [824-79-3],57, 103 Benzenesulfonamide, 4-methyl-Ar,A-bis[ 2-[ [(4-methylphenyl] sulfonyl] amino] -ethyl] -[56187-04-3], 58, 87, 97 Benzenesulfonamide, 4-methyl-A, jV-bis-[ [ [ (4-methylphenyl)sulfonyl] amino] -ethyl] -, disodium salt [52601-80-6],... 

In diselenides, the Se-Se bond length appears to be relatively constant. For example, one can compare the Se-Se bond lengths in dimethyl diselenide (2.325 A), bis-(diphenylmethyl)-diselenide (2.285 A) diphenyl diselenide (2.29 and 4,4 -(di-chlorodiphenyl)diselenide (2.33 In these same compounds the dihedral angle is 87.5°, 82°, 82 3° and 74.5°, respectively. In a crystal structure of selenium di-benzenesulfinate, QH5S(0)2SeS(0)2C5H5, the Se-S distance (2.20 A) as expected, is shorter than reported Se-Se distances. 

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