82993-63-3Relevant articles and documents
Acetamidinosulphenylation of Alkynes via Electrophilic Addition of 4'-Substituted Benzenesulphenanilides in Acetonitrile
Benati, Luisa,Montevecchi, P. Carlo,Spagnolo, Piero
, p. 1105 - 1111 (2007/10/02)
A number of 4'-substituted benzenesulphenanilides and N-methyl-4'-nitrobenzenesulphenanilide are shown to add to simple alkynes in acetonitrile in the presence of boron trifluoride-diethyl ether to give acetamidinovinyl sulphides in varying yields.Addition is largely favoured by dialkyl substitution on the alkyne and by electron-attracting anilide substituents.Moreover, the azasulphenylation adducts are produced with trans stereospecificity and high regioselectivity (Markovnikov orientation).A likely mechanism involves nucleophilic displacement by the alkyne at the activated sulphur of the anilide complexed with boron trifluoride leading to the initial formation of a thiirenium ion intermediate.Subsequent back-side attack of acetonitrile on the thiirenium ion gives a nitrilium ion which is ultimately trapped by the liberated arylamine.
Acid-promoted Decomposition of Benzenesulphenanilides and N-Aryl Bis(benzenesulphen)amides
Benati, Luisa,Montevecchi, P. Carlo,Spagnolo, Piero
, p. 2261 - 2266 (2007/10/02)
The decomposition of 4'-substituted benzenesulphanilides (1a-d) in the presence of trifluoroacetic acid (0.6 equiv.) leads to N-arylbis(benzenesulphen)amides (6a-d) in variable yields, depending on the 4'-substituent, in addition to disulphide (4) and anilines (3a-d), whereas products arising from sulphenylation of the N-aryl ring result from 3'-methoxybenzenesulphenanilide (1g).The 4'-nitro- and 3'-nitro-benzenesulphenanilides (1e,f) react with a slight excess of trifluoroacetic acid to give only (4), the thiosulphonate (5), and aniline (3e,f).The findings are interpreted in terms of possible nucleophilic attack at the S-N bond of a protonated sulphenanilide by the nitrogen or the N-aryl ring of another sulphenanilide unit, according to the nature of the substituent and its position, with displacement of aniline (3).The reaction of (1a-d) with 1.5 equiv. of trifluoroacetic acid leads to complete disappearance of the initially formed amides (6a-d) with concomitant formation of phenazines (9) and/or p-quinone di-imines (8).Similar results are obtained by using boron trifluoride-diethyl ether.Di-imines (8) and phenazines (9) are explained on the basis of a mechanism initially involving nucleophilic attack by (1) and/or (6) and/or (3) at the ortho and para positions of an intermediate cation, possibly (18A) or (18B), and loss of the disulphide (4).
The Conjugated N,N'-(Polyenediylidene)bis-sulphenamide Chromophore. Part I. N,N'-Bisarylthio-quinone Diimines
Shand, Charles A.,Thomson, Ronald H.,Greenhalgh, Colin W.
, p. 1601 - 1617 (2007/10/02)
N,N'-Bisarylthio-quinone diimines have been prepared from p-phenylenediamines and arenesulphenyl chlorieds, and from N,N'-dichloroquinone diimines and thiols.They are intensely coloured (the N,N'-dialkyl derivatives also) and exhibit Z/E isomerism in solu
