I found a few references about the allyl chloride synthesis from allyl alcohol, HCl and CuCl but haven't got access to any of the articles. I'll just post the chemical abstracts citations here, they are useful too. I'll have to look if someone had tried to use the same approach for the conversion of benzyl alcohol to benzyl chloride... Mere shaking with conc. HCl doesn't give quantitative yields.
Chimimanie, you wouldn't happen to speak about either of these refs?
Chemical Abstracts 40, 6948 (1946)Velocity of allyl chloride formation from allyl alcohol and commercial hydrochloric acid in the presence of cuprous chloride. Jean Jacques.
Bull. soc. chim. Fr. 12, 843-5 (1945). -- Mixts. of 2 cc. com. allyl alc. (d
18 0.8695) and 6 cc. HCl (d 1.19) were treated with varying amts. of CuCl, ranging from 5 to 250 mg., at 18°. Between 3.75 and 70 mg. the catalyst had a marked effect on the rate of allyl chloride (
I) formation; above and below this range the effect was relatively slight. In the absence of catalyst, no appreciable
I was formed within 48 hrs.
I is conveniently prepd. by treating 1 vol. allyl alc. with 3 vols. concd. HCl in the presence of 2-3% CuCl. The reaction is completed in less than 6 hrs. Reaction velocities are illustrated graphically.
Chemical Abstracts 25, 2412 (1931)Preparation of some allyl derivatives. R. Breckpot.
Bull. soc. chim. Belg. 39, 462-9 (1930). -- Allyl chloride is prepd. with a quant. yield and in very short time from allyl formate or allyl alc. and concd. HCl. The presence of water does not harm the reaction. CuCl is used as a catalyst, together with a small quantity of H
2SO
4. Very pure vinylacetonitrile is obtained with almost quant. yield, from allyl chloride and CuCN or from a mixt. of CuCN, concd. aq. HCl and allyl alc., or allyl formate, or both. The reaction is fast. Exptl. conditions are given.
It is also possible to synthesize allyl chloride with only allyl alcohol, conc. HCl and enough time.
J. Am. Chem. Soc 51, 225 (1929):
The Action of Sulfuric Acid in the Preparation of Certain Alkyl Halides[...] Allyl chloride and allyl bromide are commonly prepared by the aid of heat, and also by the use of sulfuric acid. These halides, as ordinarily prepared, soon develop an extremely pungent odor, becoming lachrymators, and the bromide also develops a color. A simple cold process has been worked out for preparing these halides. The high-boiling residue is very small in this process. Furthermore, one distillation gives a product which remains for months water-white and maintains a perfectly clean odor, without any trace of sharpness, when stored in the dark in an ordinary bottle. The yields are poorer than those obtained in "Organic syntheses," but our process is recommended when one wishes to sacrifice yield for quality, in making these halides for special work. The process also involves a minimum apparatus and hardly any attention, although it requires a few days' time.
Experimental Allyl Alcohol. -- Solid potassium carbonate is aded to Eastman practival allyl alcohol. The upper layer is removed and given the same treatment. After twenty-four hours it is filtered and used without distillation.
Allyl Chloride. -- The alcohol is mixed with 8 times its volume of commercial hydrochloric acid (sp. gr., 1.19) in a suitable well-corked bottle. After ten days the upper layer is washed once with 10% sodium hydroxide and twice with 15% sodium chloride, which minimizes emulsion formation. It is dried over calcium chloride and distilled. The yield of material boiling from 45-47° is from 55-65%. As an example: 204 cc. of crude alcohol with 1632cc. of acid gave 144g. of chloride.
If a small amount of halide is wanted in a hurry, the reaction is carried out in a sealed Pyrex bottle immersed in hot water (60°). Most of the yield, over 80%, is obtained in three hours.