Org. Synth. 1943, 23, 86
DOI: 10.15227/orgsyn.023.0086
trans-STILBENE
Submitted by R. L. Shriner and Alfred Berger.
Checked by W. E. Bachmann and Charles E. Maxwell.
1. Procedure
In a 4-l. beaker, equipped with a powerful mechanical stirrer which reaches nearly to the bottom, are placed 500 ml. of water and 50 g. of mercuric chloride. The stirrer is started, and 200 g. (3.06 gram atoms) of zinc dust (Note 1) is rapidly sifted into the suspension. Stirring is continued until the mercuric chloride dissolves (about 20–30 minutes). The zinc is then allowed to settle, the supernatant liquid is removed by decantation, and the amalgam is filtered and washed with 200 ml. of water. The zinc amalgam is returned to the beaker, which is now surrounded by an ice bath, and 500 ml. of 95% ethanol and 100 g. (0.48 mole) of benzoin are added. The stirrer is started, and 500 ml. of concentrated hydrochloric acid is added through a dropping funnel at such a rate that addition is complete in about 2 hours; throughout the reaction the temperature is maintained below 15°. Stirring is continued for about 2 hours more.
About 2 l. of cold water is added to the reaction mixture, and the insoluble material is collected on a Büchner funnel. The precipitate is transferred to a 2-l. beaker and extracted with two 600-ml. portions of hot ethanol. The combined extracts, on cooling, deposit long needles of stilbene which weigh 55–59 g. and melt at 116–121°. These are filtered with suction and are recrystallized from 600 ml. of 95% ethanol. The yield is 45–48 g. (53–57%) of colorless needless melting at 123–124°.
2. Notes
1.
The
zinc dust used was obtained from J. T. Baker and Company.
3. Discussion
The procedure described is essentially that of Ballard and Dehn.
1 Stilbene has also been prepared by reduction of
desoxybenzoin,
2 benzaldehyde3 and
benzil;
2,4 by dehydrogenation of
ethylbenzene,
5 toluene,
5,6,7 and
bibenzyl;
6,8 by alkaline reduction of
phenylnitromethane,
9 phenylnitroacetonitrile,
9 and
desoxybenzoin;
10 by distillation of
benzyl sulfone,
11 benzyl sulfide,
11,12 calcium cinnamate,
13 cinnamic acid,
14 phenyl cinnamate,
15,16 and
diphenyl fumarate,
11 by dehydrohalogenation of
α,α'-dichlorobibenzyl17 and
benzyl chloride;
18 by dehalogenation of
α,α,α',α'-tetrachlorobibenzyl19 and
benzal chloride;
20 by the coupling of
cinnamic acid and
phenyldiazonium chloride;
21 by dehydration of
benzylphenylcarbinol,
17,22 benzyl ether,
23 and
benzyl alcohol;
23,24 by treatment of
benzaldehyde ethyl mercaptal with
Raney nickel;
25 by pyrolysis of
methyl benzyl dithiocarbonate;
26 and by catalytic desulfurization of
trithiobenzaldehyde.
27 The diazonium coupling reaction
21 appears to have the widest applicability for the synthesis of substituted stilbenes.
This preparation is referenced from:
Appendix
Chemical Abstracts Nomenclature (Collective Index Number);
(Registry Number)
Desoxybenzoin
ethanol (64-17-5)
hydrochloric acid (7647-01-0)
phenyldiazonium chloride
benzaldehyde (100-52-7)
Raney nickel (7440-02-0)
Benzil (134-81-6)
Benzoin (119-53-9)
toluene (108-88-3)
zinc (7440-66-6)
benzyl chloride (100-44-7)
Benzyl alcohol (100-51-6)
benzyl ether (103-50-4)
mercuric chloride (7487-94-7)
ethylbenzene (100-41-4)
cinnamic acid (621-82-9)
benzal chloride (98-87-3)
Phenylnitromethane (622-42-4)
stilbene
α,α'-dichlorobibenzyl
Phenyl cinnamate (2757-04-2)
bibenzyl (103-29-7)
phenylnitroacetonitrile
benzyl sulfone (620-32-6)
calcium cinnamate
diphenyl fumarate
benzaldehyde ethyl mercaptal
methyl benzyl dithiocarbonate
trithiobenzaldehyde
Benzyl sulfide (538-74-9)
trans-Stilbene (103-30-0)
α,α,α',α'-tetrachlorobibenzyl
benzylphenylcarbinol (614-29-9)
Copyright © 1921-, Organic Syntheses, Inc. All Rights Reserved