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91.
92.
The structure of stable [C9H11]+ ions from different model compounds with the molecular formula C9H11Cl has been estimated by energy measurements. It has further been shown that acetylenic compounds cyclise to form aromatic ions in the range of the appearance potentials.  相似文献   
93.
Zusammenfassung Aus Anilinen, die im aromatischen Ring mit CH3, CH3SCH2, CH3O, Cl, Br oder NO2 substituiert sind, und Sulfoxiden wird in Anwesenheit von P4O10 und Triäthylamin eine Reihe von N-Aryl-S,S-dialkylsulfimiden erhalten. Diese Reihe umfaßt Verbindungen mit CH3-, C2H5- und –(CH2)4-Gruppen am Schwefelatom. Das Sulfimid aus Mesidin lagert sich—formal analog zu einerSommelet—Hauser-Umlagerung—zum 2,4,6-Trimethyl-2-methylthiomethylcyclohexa-3,5-dien-1-imin um.
Methylthiomethylation of anilines and phenols, III: Preparation of N-aryl-S,S-dialkylsulfimides
The synthesis of a number of N-aryl-S,S-dialkylsulfimides by reaction of anilines with sulfoxides in presence of P4O10 and triethylamine is given. This series includes compounds with CH3-, CH3SCH2-, CH3O-, Cl-, Br- and nitro-groups attached to the aromatic nucleus, resp., and with CH3-, C2H5-or–(CH2)4-groups on the sulfur atom. The sulfimide obtained from mesidine is rearranged in formal analogy to aSommelet-Hauser rearrangement to 2.4.6-trimethyl-2-methylthio-methylcyclohexa-3.5-dien-1-imine.


Als 1. Mitt. soll gelten:P. Claus, Mh. Chem.99, 1034 (1968).

2. Mitt.:P. Claus undW. Vycudilik, Tetrahedron Letters1968, 3607.  相似文献   
94.
Abstract

N-Aryl-S,S-dialkylsulfimides, 1, with R1 = alkyl other than CH3, have been rearranged by heating in ethanol yielding o-alkylthiomethyl-anilines, 2, as main products. Isomeric o-methylthioalkyl-anilines, 14, are formed in minor amounts only. Reactions of sulfimides, 1, with R1 = CH3, with certain alkylating or acylating agents yielded o-methylthiomethylated, N-alkylated or -acylated products 9. Mechanistic considerations are discussed. The rearrangement of sulfimides 1 has been assumed to occur via [2,3]-sigmatropic reactions of intermediate azasulfonium ylids 3. Attempts to resolve (+)-camphor-10-sulfonates of N-aryl sulfimides failed, but optically active N-aryl sulfimides could be obtained by reaction of anilines with optically active sulfoxides and P4O10. Optically active 2,6-disubstituted sulfimides, 1, could be rearranged in ethanolic KOH to yield optically active cyclohexadienimines 12, indicating a transfer of asymmetry from sulfur to carbon and supporting the assumption of a sigmatropic rearrangement.  相似文献   
95.
96.
5‐Alkyl‐4‐benzyl‐1,3‐dihydroimidazol‐2‐ones ( 3a‐d ) and 5‐alkyl‐4‐benzyl‐1,3‐dihydroimidazole‐2‐thiones (7a‐d) were prepared via Dakin West reaction on DL‐phenylalanine with the appropriate aliphatic acid anhydrides followed by hydrolysis and reaction with potassium cyanate or potassium thiocyanate. Compounds 3a‐d were alkylated with ethoxymethyl chloride to give the alkylated imidazoles 5a‐d which were considered analogues of Emivirine with deletion of carbonyl group at the 4‐position. Alkylation of 7a‐d afforded the corresponding S‐alkylated derivatives 8a‐p which in a similar way were considered analogues of S‐DABO. However all the imidazole derivatives were devoid of activity against HIV.  相似文献   
97.
Symmetry breaking is an important phenomenon connected to the excitation of core electrons in molecules. The fundamental question of whether inner-shell electronic-state orbitals are delocalized, and what the underlying mechanism for breaking the symmetry of a molecule upon dissociation are the subject of much debate, especially for the case of diatomic molecules. One method for studying molecular fragmentation, which is based upon a symmetry picture, is multicoincidence ion spectroscopy. Here we give a brief presentation of some of the applications of this technique, where symmetry, nuclear motion and the temporal signature are of importance.  相似文献   
98.
The canonical quantization for N = 1 supergravity in the context of gravitational minisuperspace described by Gowdy T 3 and Bianchi class A cosmological models is analyzed in order to search for physical states. There are indeed physical states in the minisuperspace sector of the theory. This fact entails that the non-physical states conjecture has a restricted validity, and in consequence it cannot be considered a general result.  相似文献   
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