The formula of benzene (C6H6), caused a mystery for some time after its discovery, as no proposed structure could take account of all the bonds (carbon usually forms four single bonds and hydrogen one). The chemist Kekulé was the first to deduce the ring structure of benzene; after years ...
are attached,the average ring current values are higher than that of the cases when electron-donating substituents(+ R effect:NHMe,NMe2,OH,SH,etc.)are attached.The same trend was also observed for the anisotropy values of the induced current density(ACID)analysis.The isosurface contour diagram...
The manner in which specific substituents influence the orientation of electrophilic substitution of a benzene ring is shown in the following interactive diagram. As noted on the opening illustration, the product-determining step in the substitution mechanism is the first step, which is also the slow...
substituents of the starting naphthalene, as they control the relative stability of thecarbenium ionsand the possible rearrangements. Dihydrophenanthrenones,spiro compounds, and anthracenones are obtained depending on the R group, the position of the side chain in the naphthalene ring, and the ...
A simplified out-of-plane valence force field has been developed for some benzene derivatives that have unsaturated substituents. The molecules treated in this study are benzene, styrene, benzaldehyde, ethynylbenzene and m- and p-diethynylbenzenes. In the force field we have used two different ap...
4.32.4.1.2.(iii) Derivatives containing O- or S-linked substituents Treatment of 4-methylbenzene-1,2-dithiol (270) in methyl chlorodithioformate with 70% perchloric acid forms the 5-methyl-2-methylthio-1,3-benzodithiolylium perchlorate (285) in 33% yield 〈64JOC2877〉. Sign in to downlo...
where the substituents are as defined below: R1is hydrogen, C1-C6-alkyl, R2is C1-C6-alkyl, R3, R4, R5are hydrogen, C1-C6-alkyl, or R4and R5together form a bond, R6is a heterocyclic ring, n is 0, 1 or 2; which comprises preparing an intermediate of the formula VI ...
The relative energetics are discussed in terms of potential surface diagram having the benzene ring deformation as the "reaction coordinate". Comparison with the anthracene isomerization is made and the effect of substituents is pointed out.doi:10.1007/BF01374576Malte von Arnim...
the two substituents of the ring cannot simultaneously represent respectively -NO2 and -CH3 , with the proviso for the following particular cases : a) when R8 represents one of the following radicals : see diagramm : EP0007880,P13,F2 in which n=0, 1 or 2 or an ester thereof, one at ...
Anionic statistical CPA represent substituted polyenes with alternating –H, –PhC≡CH, –C≡CPh and –Ph substituents. The nature of the alternation of these substituents will depend on the following factors: the ratio of monomers in the copolymers; a different combination of two types of attach...