Synthesis and NMR data of some variously substituted diphenylmethanes and dibenzylbenzenes

Abstract

Fifty-four new compounds-methyl and halo derivatives of diphenylmethane and o,rn,p-dibenzylbenzene-were prepared under mild conditions. The identity of compounds prepared was established by nmr, and spectral assignments are reported.

Synthesis and conformations of dibenzylanthracenes. Evidence for the 1,4-benzylation of anthracene

“…These data rule out all alternative structures, but the 1,4 and 2,3 types (1,5 type cannot account for the 6.40 ppm singlet and for the AA'BB' system; 1,2 type might account for the AA'BB' system but not for the 6.40 ppm singlet, etc.). In fact, 1,4 and 2,3 type structures should give roughly the same nmr pattern (i.e., the four anthracene protons 5 to 8 should appear as an AA'BB' system, protons 9 and 10 as a singlet, and protons 2 and 3 or 1 and 4, respectively, should appear as a singlet).…”

“…Structure Proof and Conformational Properties. -The uv and nmr spectral characteristics of compounds [1][2][3][4] are reported in Table I, together with those of some reference compounds. The uv spectra of compounds 1 and 2 show a definite red shift in the anthracene absorption bands (300-380 mp), which, as well recognized,12 is characteristic of the 9,10-disubstituted anthracenes.…”

“…Syn., 25, 65 (1945). 9.10-Bis(2,5-dimethylbenzyl(anthracene (1).-This product was synthesized in one of two ways: by reacting 2,5-dimethyIbenzyl chloride (7.7 g, 0.05 mol) with anthracene (8.90 g, 0.05 mol) dissolved in nitroethane (200 ml) at 50°with stannic chloride as a catalyst (0.5 ml 0.0043 mol) for 2 hr [yield 1.6 g (15%)]; or, in good yield (3.3 g, 80%), by reacting 9,10-bis(chloromethyl (anthracene (2.75 g, 0.01 mol) with p-xylene (50 g, 0.42 mol) in nitroethane (50 ml) at 100°for 2 min, with stannic chloride (0.1 ml, 0.00087 mol) as a catalyst. In both cases the mixture was poured into methanol (1:10).…”