Tert-butyl sulfinamide

Using Vinyl Sulfonium Salts Aggarwal and coworkers have reported that the reaction of the a-, p-, or Y-aminoaldehydes 68 with diphenyl vinyl sulfonium salt 69 in the presence of a base gave the fused bicyclic heterocycles 70 (Scheme 4.15) [24]. This methodology has been extended to the asymmetric synthesis of seven-membered hexahydroazepine. Condensation of the hemiaminal 71 with (/ )-tert-butyl-sulfinamide [25] afforded the aminal 72, which was in equilibrium with sulfinylimine 73. Reaction of 72 with diphenyl vinyl sulfonium salt 69 in DMF using NaH as a base furnished the aziridine-fused hexahydroazepine 74 in 68% yield as a 3 1 mixture of diastereomers. Subsequent A-deprotection afforded the known chiral aziridine 75, an intermediate in the synthesis of (-)-balanol (76). 

Radical cyclization of acyclic sulfinamides 239 provides easy access to cyclic sulfinamides 241 <06AG(E)633>. Conceivably, the reaction pathway involves thiophilic attack by the aryl radical with a concomitant or successive expulsion of the p-tolyl or tert-butyl radical. 

Naskar, D., Roy, A., Seibel, W. L., Portlock, D. E. Hydroxylamines and sulfinamide as amine components in the Petasis boronic acid-Mannich reaction synthesis of N-hydroxy or alkoxy-a-aminocarboxylic acids and N-(tert-butyl sulfinyl)-a-amino carboxylic acids. 

Scheme 1034. The synthesis of (l/ )-l-phenylpropylamine hydrochloride. Beginning with tert-butyl disnlfide, oxidation with hydrogen peroxide in the presence of VO(acac>2 and (5 )-2-(A -3,5-di-f-butylsaIicylidene)amino-3,3-dimethyl-l-butanol prodnces the chiral sulfinate (5 )-f-butyl-f-butanethiosulfinate. Then, addition of the sulfinate in THF (oxocyclopentane, THF) to a suspension of lithium amide (L1NH2) in Uquid ammonia (NHs )) generates K)-t-butanesulfinamide. The optically active sulfinamide reacts with propanal to form the corresponding sulfinimine. Reaction of the latter with phenylmagnesium bromide (CtllsMgBr) in ether yields A -(l-phenylpropyl)-f-butanesulhnamide and hydrolysis in methanolic HCI generates the corresponding (IR)-l-phenylpropylamine hydrochloride. The cartoon drawing of the presumed cyclic transition state is used to account for the stereochemical outcome. But see Hose, D. R. I Mahon, M. E Molloy, K. C. Raynham, T Wills, M. /. Chem. Soc. Perkin Trans. 7,1996, 7, 691.

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