Bromobenzene structure

Fig. 40a, b. NSE spectra of a dilute solution under 0-conditions (PDMS/ d-bromobenzene, T = = 357 K). a S(Q,t)/S(Q,0) vs time t b S(Q,t)/S(Q,0) as a function of the Zimm scaling variable ( t(Q)t)2/3. The solid lines result from fitting the dynamic structure factor of the Zimm model (s. Tablet) simultaneously to all experimental data using T/r s as adjustable parameter. 

The crossover from 0- to good solvent conditions in the internal relaxation of dilute solutions was investigated by NSE on PS/d-cyclohexane (0 = 311 K) [115] and on PDMS/d-bromobenzene(0 = 357K) [110]. In Fig. 45 the characteristic frequencies Qred(Q,x) (113) are shown as a function of t = (T — 0)/0. The QZ(Q, t) were determined by fitting the theoretical dynamic structure factor S(Q, t)/S(Q,0) of the Zimm model (see Table 1) to the experimental data. This procedure is justified since the line shape of the calculated coherent dynamic structure factor provides a good description of the measured NSE-spectra under 0- as well as under good solvent conditions. 

Problem 13.11 For the following pairs of halides and carbonyl compounds, give the structure of each alcohol formed by the Grignard reaction, (a) Bromobenzene and acetone, (b) p-Chlorophenol and formaldehyde, (c) Isopropyl chloride and benzaldehyde. (d) Chlorocyclohexane and methyl phenyl ketone. 4... 

The nomenclature of benzene derivatives is described in Sec. 4.6. Common names and structures to be memorized include those of toluene, styrene, phenol, aniline, and xylene. Monosubstituted benzenes are named as benzene derivatives (bromobenzene, nitrobenzene, and so on). Disubstituted benzenes are named as ortho- (1,2-), meta- (1,3-), or para- (1,4-), depending on the relative positions of the substituents on the ring. Two important groups are phenyl (C6H5-) and benzyl (C6H5CH2-). 

However, if halogen atoms are deactivating the ring due to inductive effects, they should not direct substitution to the meta position like other electron-withdrawing groups. Consider the nitration of bromobenzene. There are three resonance structures for each of the three intermediates leading to these products, but the crucial ones to consider are those which position a positive charge next to the substituent. 

The broinination of bromobenzene gives three dibromobenzenes in the yields shown in the following equation. A shows three peaks in its l3C-NMR spectrum. B shows two, and C shows four. Show the structures of A, B, and C. 

Write structural formulas for (a) benzene, (b) toluene (methyl benzene), and (c) bromobenzene. 

Benzene yields only one monosubstitution product C HsY. Only one bromobenzene, C HsBr, is obtained when one hydrogen atom is replaced by bromine similarly, only one chlorobenzene, C6H5CI, or one nitrobenzene, QH5NO2, etc., has ever been made. This fact places a severe limitation on the structure of benzene each hydrogen must be exactly equivalent to every other hydrogen, since the replacement of any one of them yields the same product. 

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