Dimethylbenzenes

Aromatics - Benzene, Methylbenzene (Toluene) Dimethylbenzene (Xylenes) Naphthenes - Cyclopentane, Cyclohexane... 

Chromic acid oxidation of 4 tert butyl 1 2 dimethylbenzene... 

Nitration of 1 4 dimethylbenzene (p-xylene) gives a single prod uct having the molecular formula C8H9NO2 m high yield What is this product... 

Bromo 1 3 dimethylbenzene is inert to nucleophilic aromatic substitution on treatment with sodium amide in liquid ammonia It is recovered unchanged even after extended contact with the reagent Suggest an explanation for this lack of reactivity... 

XYLENES AND ETHYLBENZENE] (Supplement) m-Xylene [108-38-3], (See also 1,3-Dimethylbenzene.)... 

The PMBs, when treated with electrophilic reagents, show much higher reaction rates than the five lower molecular weight homologues (benzene, toluene, (9-, m- and -xylene), because the benzene nucleus is highly activated by the attached methyl groups (Table 2). The PMBs have reaction rates for electrophilic substitution ranging from 7.6 times faster (sulfonylation of durene) to ca 607,000 times faster (nuclear chlorination of durene) than benzene. With rare exception, the PMBs react faster than toluene and the three isomeric dimethylbenzenes (xylenes). 

Hexanol n-Hexyl alcohol 92 C(3Hi40 m-Xylene 1,.3-Dimethylbenzene 70 QHio... 

Hexanone Methyl n-butyl ketone 127 CsHijO p-Xylene 1,4-Dimethylbenzene 71 QHio... 

N,N-Dimethylaniline) Dimethylbenzene, see Xylene 1,3-Dimethylbutyl acetate Dimethyl carbamoyl chloride Dimethyl-1,2-dibromo-2,2-dichloroethyl phosphate, see Naled Dimethyl ether N-N-Dimethylethylamine Dimethylethoxy silane Dimethylformamide SK... 

Dimethylbenzene, see Xylene Dimethyl-1,2-dibromo-2-dichloroethyl phosphate, see Dibrom ... 

At 320 °C, cesium tetrafluorocobaltate converts benzotrifluoride to /n-fluo-robenzotrifluoride, 2f/-heptafluorotoluene, octafluorotoluene, pertluoro-l -meth-ylcyclohexene, and perfluoromethylcyclohexane [29] l,3-Bis(trifluoromethyl)-benzene is convened at 420 °C to 4,5,6-trifluoro-l,3-bis(trifluoroethyl)bcnzene, perfluoro-l,3-dimethylbenzene, and perfluoro-l,3-dimethylcyclohexane [29], p-Xylene gives at 350 °C l,4-bis(difluoromethyl)tetrafluorobenzene, 1-di-fluoromethyl-3-trifluoromethyltetrafluorobenzene, perfluoro-1,3-dimethyl-benzene, and perfluoro-1,3-dimethyloyclohexane... 

The 200-MHz H NMR spectrum of 1,4-dimethylbenzene looks exactly like that of CH3OCH2CN except the chemical shifts of the two peaks are 8 2.2 and 8 7.0. Assign the peaks to the appropriate protons of 1,4-dimethylbenzene. 

If several groups are attached to the benzene ring, their names as well as their relative positions should be indicated. For example, dimethylbenzene or xylene, CgH (CH,)2, has three geometric isomers, with prefixes ortho-, meta-, and para-, indicating the relative positions of the two methyl groups. 

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