Sulfilimines cyclic

On the other hand, deprotonation of cycloadduct 76 with sodium hydride in acetonitrile at 0°C afforded cyclic sulfilimine 78, the so-called 1,2-azathiabenzene derivative, together with a spiro compound 79 (see Equation (21) and Table 11) <1999TL1505>. 

In addition the structure of the 1,2-azathiabenzene 78 was also confirmed by chemical evidence as shown in Scheme 10. Protonation of 78a (R1 = R2 = Me) with 70% perchloric acid yielded the corresponding cyclic amino sulfonium salt 82a in 87% yield, but not the starting sulfonium compound 76a, suggesting predominance of sulfilimine structure 78a rather than cyclic sulfonium ylide stmcture 80a. Thus, compound 78 could be recognized as the first example of a 1,2-azathiabenzene having sulfur at a bridgehead position. A proposed mechanism for the formation of 78 and 79 is shown in Scheme 9. The most acidic proton adjacent to sulfur in 76 is deprotonated with... 

Cyclic sulfilimines are considered useful reagents in organic synthesis <00JOC8086 03JOC9574>. The chemistry of cyclic sulfilimines has been studied extensively since the... 

A similar reaction is observed for cyclic sulfilimines. For example, octafluorotetrahydro-1//-l/l4-thiophene-1-imine is easily oxidized to the 1-iminc 1-oxide (sulfoximine) by 3-chloro-peroxybenzoic acid (Table 19).307... 

Dibenzodithiazocin 47 can be transformed into cyclic sulfilimine 84 by reaction with a mixture of acetic anhydride-pyridine at 100°G (Equation 24) <1995CC1069>. No mechanism is given for this transformation. 

Treatment of thietanes with chloramine T gives N-tosylsulfilimines, for example, 126. Acyclic and five-, six-, and seven-membered cyclic sulfides all react more rapidly than thietane. The mechanism has been investigated. The IR stretching vibrations of the S-N-SO2 system are at 948 and 759 cm", and the nmr spectrum of 3,3-dimethylthietane 1-tosylsulfilimine in benzene and chloroform suggests an equatorial conformation for the sulfilimine. Oxidation of this sulfilimine gives the sulfoximine derivative, 127. The two diastereomeric tosyl-sulfilimines of 3-methyl-3-phenylthietane complex at nitrogen with silver ion. ... 

Although widely used as a dehydration reagent, Martin s sulfurane is also known to facilitate amide cleavage reactions,7 cyclic ether (including epoxide) formations,8 and sulfilimine syntheses.9 In the 1970s Martin demonstrated all of these transformations in his series of papers outlining the reactivity of the title sulfurane. 

Attempts to form a penicillin sulfilimine by reaction of the penicillin (378) with chloramine T resulted in a rearranged product (379) (Campbell and Johnson, 1974). This product presumably arose from the initially formed sulfilimine (380) which, on C-5—S bond cleavage and subsequent ring closure, resulted in the cyclic sulfilimine (381). Reaction with excess chloramine afforded the observed product. Thermal treatment of 379 resulted in an electrocyclic rearrangement to the azetidinone (382) (Campbell and Johnson, 1975). 

N-monosubst. 27, 294 cyclic 31,281 Sulfimines s. Sulfilimines Sulfinamidines s. N-Acylsulfinamidines Sulfinic acid amides... 

R.E. Dolle, C.-S. Li, A.N. Shaw, Concomitant [2+3]-sigmalropic rearrangement of sulfilimines and intramolecular N-alkylalion. S)mthesis of 2-vinyl-substituted cyclic amines. Tetrahedron Lett. 30 (1987) 4723-4726. 

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