04-28-02 20:26
No 302617
Does anybody know how too synthesize Benzal Chloride.
Before you start Flippin I've searched but haven't find anything.
You've gotta love me.
(Hive Addict)
04-28-02 20:59
No 302628
By bubbling chlorine gas into toluene with UV light.
First you get benzyl chloride, and then with further chlorination you get benzal chloride, then lastly you will get benzotrichloride.
C6H5.CH3 + Cl2 = HCl + C6H5.CH2Cl (Benzyl Chloride)
C6H5.CH2Cl + Cl2 = HCl + C6H5.CHCl2 (Benzal Chloride)
C6H5.CHCl2 + Cl2 = HCl + C6H5.CCl3 (Benzotrichloride)
The procedure will be the same as :
../rhodium /benzylc
Except that the boiling point of benzal chloride is 207°C, and this change to the procedure :
An alternative method of determining the completion of the reaction is to weigh the flask and toluene, and to stop the passage of chlorine when the increase in weight is 74 g.
Nobodys home
(Hive Bee)
04-28-02 21:24
No 302635
(Rated as: excellent)
From Megalomania's Controversial Chem Lab:
http://roguesci.org/megalomania/
Benzal Chloride
Place 58mL (50g) of toluene in a round bottom 100mL flask. Attach a Clasien adapter to the flask. On the angled arm of the adapter, attach a condenser set up for refluxing. Since excess chlorine gas will be released from the top of the condenser, affix a one-holed stopper with a short length of glass tubing connected to a long hose, direct the hose to a well ventilated area. On the straight arm of the adapter, attach a length of glass tubing with a bubbler at the end that extends below the surface of the toluene. The top of this tube is connected to a chlorine generator.
Position the setup such that the flask is in direct sunlight, or very strong light. Sunlight is superior. Heat the toluene to boiling while a current of dry chlorine gas is bubbled in, the chlorine can be dried by passing it through two drying bottles filled with concentrated sulfuric acid. The course of the reaction is best judged by weighing the product; the reaction is complete when the toluene has increased by 40g, the total weight being 90g. By weighing the flask beforehand, and periodically interrupting the flow of chlorine to cool and weigh the flask, the completeness of the reaction can be determined. Without weighing, it is very difficult to gauge this reaction as the length varies greatly.
In the summer, in direct midday sunlight, the reaction is complete in a few hours. In winter, or low light, the reaction needs 12-24 hours to complete. Adding 4g of phosphorus pentachloride to the toluene can enhance the reaction. The crude benzal chloride thus obtained can be directly used to make benzaldehyde.
I assume that you need it for benzaldehyde synthesis, so I'll post it righ here. It is from the same site as benzal chloride preparation.
Benzaldehyde from Benzal Chloride
To prepare benzaldehyde, start with the crude benzal chloride obtained from its Synthesis. Into a round-bottomed flask with the benzal chloride, add a solution of 500mL of water and 150g of calcium carbonate. Set the flask up for reflux and heat for 4 hours on an oil bath. Keep the oil bath at 130° C by checking the oil itself with a thermometer.
After refluxing, steam distill the product to obtain crude benzaldehyde oil. (The portion that did not distill over contains some benzoic acid. It can be discarded, or purified by filtering while hot through a piece of fluted filter paper, then adding concentrated HCl to the filtrate. On cooling the benzoic acid will precipitate, it is filtered and recrystallized from hot water.) The crude benzaldehyde oil is treated with a concentrated solution of sodium bisulfite, after shaking for a long time the oil should have dissolved into solution. If any crystals happen to form during the shaking, add water until they dissolve.
After most of the oil is dissolved, filter the solution over fluted filter paper, and then treat the filtrate with sodium carbonate until it is strongly alkaline. This liquid is now steam distilled to obtain pure benzaldehyde. The product can be further purified by mixing with ether, letting the ether evaporate, and distilling (normal, not steam) the benzaldehyde.
If you have obtained benzaldehyde from other sources, it must be purified if it is anything less than ACS grade. It should be washed with sodium carbonate solution, dried, and distilled with minimum atmospheric exposure. Only the fraction collected at 178-180° C is kept.
Life without chemistry would be a mistake.
(Chief Bee)
04-28-02 23:18
No 302685
The land beneath our feet, the air in our lungs, the trees on the horizon.
All are sources of chemicals.
No legislation can ban them, no government can control them, no soldier can take them.
If industry can do it, so can I.
(Hive Bee)
04-29-02 04:34
No 302808
SWIM is planning on trying that synth. What determines the amount of chlorination (1x,2x,or 3x)? Durration of exposure? For example is there any di or tri chlorinated products before the major componet is preceedingly chlorinated?
Do mirrors reflect UV light? SWIM is trying to be industrius and wants to chlorinate toluene on a large scale - 5 gallon water jugs in a field, each with chlorine gas feed, surrounded by a circle of large floor mirrors proped up to catch and focus the sunlight.
Input please, can to much UV help or hurt?
Can a bee be visa vis its entity when half a bee philosophically must ipso facto half not be?
(Hive Bee)
04-29-02 07:32
No 302875
Benzaldehydes are produced by heating the corresponding benzal chloride containing less than 1% anhydrous ZnCl2 to above 100 DEG C. (preferably 105 DEG C.-135 DEG C.) and adding water at substantially the rate at which it reacts with the benzal chloride. In examples (1) benzaldehyde is obtained from benzal chloride and (2) o-chlorobenzaldehyde from o - chlorobenzalchloride, p-Chloro- and 2 : 6-dichloro-benzaldehydes, and o-, m- and p-tolualdehydes are also mentioned.
GB899953 (http://l2.espacenet.com/espacenet/viewe
You've gotta love me.
(Hive Addict)
04-29-02 14:08
No 302967
Yes most ordinary mirrors reflect UV.
UV lamps and flouresent tubes can be bought from aquarium suppliers, disco suppliers, and also electrical component suppliers (UV PCB developing).
And how about a UV light bulb :
Nobodys home
(Hive Bee)
04-29-02 16:20
No 302988
Why bother with black lights though? I mean the sun is a powerful source and would probably produce the most efficient use of Cl2. I cant wait to see how my sun catcher idea works, i will get back with that.
Can a bee be visa vis its entity when half a bee philosophically must ipso facto half not be?
(Hive Bee)
04-30-02 18:19
No 303373
How is fractionated OTC toluene for this reaction? Its getting harder to find but i can still get it, im just wondering if fractionating it will seperated it enough from its other componets to make it usable for this.
Can a bee be visa vis its entity when half a bee philosophically must ipso facto half not be?
(Distinctive Doe)
04-30-02 18:36
No 303376
"Adding 4g of phosphorus pentachloride to the toluene can enhance the reaction."
Or a pinch of matchbox RP, this reaction can bee done with no UV in the same way by adding a catalytic amount of RedP.
I posted an abstract sometime ago.
Or you can use Lithium Hypochlorite and NO UV
Those who give up essential liberties for temporary safety deserve neither liberty nor safety
(Hive Bee)
04-30-02 22:23
No 303453
Foxy do you have a writup for Lithium hypochlorate? Rhod has a process on his site that uses bleaching powder but it isnt to specific. Thanks
Can a bee be visa vis its entity when half a bee philosophically must ipso facto half not be?
(Distinctive Doe)
04-30-02 23:39
No 303485
time to learn about tfse?
Post 36700 (CHEM_GUY: "Re: benzyl chloride from hypochlorite salts", Chemistry Discourse)
Post 101658 (Scooby Doo: "Re: Benzyl Chloride", Chemistry Discourse)
Post 108293 (dormouse: "benzyl chloride from toluene? -drone 342", Novel Discourse)
Post 228452 (foxy2: "Re: Benzaldehyde -> Benzyl Chloride (cold)", Chemistry Discourse)
Those who give up essential liberties for temporary safety deserve neither liberty nor safety
(Hive Bee)
05-01-02 03:19
No 303561
Oh you silly fox, yup did read all of thoes, i have yet to find an article on lithium hypochlorate, i understand the the molar amounts would be the same for that reaction - but for the purpose of discusion it would be interesting to have seen the yield variations of different alkali metal hypochlorate chems.
Anyways the writup on Rhods site is exactly what all thoes posts indicate.
Can a bee be visa vis its entity when half a bee philosophically must ipso facto half not be?
(Hive Bee)
05-01-02 03:36
No 303569
Benzyl Chloride cant be that suspisious to order from the right supplier.
Reasearched uses include manufacture of perfumes, dyes, synthetic tannins, artificial resins, photography, pesticides and gasoline gum inhibitors. If one found a company with specific areas of interest in supplying raw materals to any one of these industries one might have luck. any input?
Can a bee be visa vis its entity when half a bee philosophically must ipso facto half not be?
(Hive Addict)
05-01-02 03:38
No 303571
You wont get the right results using lithium hypochlorate, maybe you mean hypochlorite !
Lithium hypochlorite is well expensive compared to calcium or sodium hypochlorite anyway.
..........
Is it just a case of using more hypochlorite to achieve benzal chloride ?
Nobodys home
(Hive Prodigy)
05-01-02 04:31
No 303595
Benzyl Chloride is list 2 in the US with few "common" uses, unlike toluene, which is also list 2. US bees should not order benzyl chloride from US suppliers in my opinion.
PrimoPyro
Vivent Longtemps La Ruche!
(Hive Addict)
05-01-02 17:36
No 303804
If the end product that you require is benzaldehyde then this can also be made from benzyl chloride :
Benzyl chloride is boiled under reflux for several hours with a solution of cupric nitrate or lead nitrate, when hydrolysis and oxidation occurs:
C6H5.CH2Cl + H2O = C6H5.CH2OH + HCl
C6H5.CH2OH + O = C6H5.CHO + H2O
A stream of carbon dioxide is usually passed through the mixture to remove oxides of nitrogen. The benzaldehyde is extracted with ether, dried with anhydrous calcium chloride, and distilled. If necessary it can be purified further by forming a crystalline addition compound with sodium bisulphite and distilling this with dilute sulphuric acid.
Nobodys home
(Newbee)
05-01-02 18:12
No 303816
Although not explicitly scheduled in EU-Order 3677/90, it's a known amphetamine precursor and therefore watched in EU too.
(Stoni's sexual toy)
05-02-02 09:18
No 304112
This thread is a nice example of why spelling IS important!
chloride MCl
hypochloride MClO
hypochlorite (?) MClO2
hypochlorate doesn't exist
chlorate MClO3
perchlorate MClO4
I'm not fat just horizontally disproportionate.
(Hive Prodigy)
05-02-02 16:43
No 304184
chloride MCl
hypochloride MClO
hypochlorite (?) MClO2
hypochlorate doesn't exist
chlorate MClO3
perchlorate MClO4
And I assume you mean hypochlorite and chlorite, respectively, Os?
ClO- is hypochlorite, ClO2- is chlorite. I know you know this heh, so even you must make spelling errors from time to time.
PrimoPyro
Vivent Longtemps La Ruche!
(Stoni's sexual toy)
05-02-02 17:34
No 304201
Yup, not my fault that you Americans spell it all wrong!
I'm not fat just horizontally disproportionate.
(Hive Addict)
05-02-02 18:14
No 304218
I can't seem to find any references to hypochloride salts in any of my books, do these salts really exist ?
Nobodys home
(Chief Bee)
05-02-02 18:49
No 304230
No, that was a misspelling - Os meant "hypochlorite".
(Hive Bee)
05-03-02 04:26
No 304434
Can 3,4-(Methylenedioxy)toluene be subed in to make 5-chloro-1,3-benzodioxole in the procedure described that uses Cl2?
Can a bee be visa vis its entity when half a bee philosophically must ipso facto half not be?
(Chief Bee)
05-03-02 13:54
No 304566
If you substitute the toluene with 3,4-Methylenedioxytoluene the product is 3,4-Methylenedioxybenzyl chloride, not 5-chloro-1,3-benzodioxole (which has no methyl group).
(Stranger)
05-04-02 02:11
No 304720
(Rated as: excellent)
I'm pseudonymous. I wear these shades ?O^O? so people won't see how incognito I am.
I had 100 g benzal chloride on hand. I put it in a 1000 ml RB flask, with 500 ml water and 120 g Ca(OH)2, slaked lime, and refluxed for 4 hours, then steam distilled the benzaldehyde. It proves out one of the assertions made in this thread; unfortunately, things happened in the run to make yield suffer, and the the initial oil separation from underneath the water layer amounted to only 22.9 g of benzaldehyde. Well, it doesn't seem enough to go on to the next stage of what I wanted to prove, under my working conditions, so it needs to bee supplemented. Benzaldehyde can also be made by the MnO2 / H2SO4 oxidation of benzyl chloride or toluene itself, and of course by partial oxidation of benzyl alcohol. Benzal chloride, topic of this thread, is the old industrial standard predecessor of benzaldehyde, which is available from benzal chloride by hydrolysis either acid or basic.
Instead of the direct chlorination of toluene, my benzal chloride was brewed in a glass coffeepot, with "saran" stretched over the top to provide refluxing, or let's say retard evaporation of toluene, in a mix of 1:1.66 toluene to calcium hypochlorite by mass. (This was after US 1280612 Post 36700 (CHEM_GUY: "Re: benzyl chloride from hypochlorite salts", Chemistry Discourse) which tells how to make benzyl chloride in a coffeepot outdoors, with a 1:1 ratio of toluene to Ca hypochlorite.) The rxn calls for close temperature control, so use your hotplate. Preferred temperature for the patentee was just over 100°, but for us 90° is better, and our coffeepot run lasts several hours, instead of just an hour. Do not let the toluene reach its actual boiling point, or you have got a thermal runaway, bad smoke, might break glass or give other problems. Allow a moderately vigorous reaction, approximately 75° climbing to 95°. For benzyl chloride it produces just under the 30% conversion of toluene claimed in the patent. Increase the proportion of pool shock tablets to toluene for a benzal chloride run, and there is a higher conversion, but you have toluene and all three chlorinated derivatives for later fractionation.
Now let's pay a little closer attention to what benzaldehyde can do for us: prepare for a surprise. Benzaldehyde condensed with acetaldehyde gives cinnamaldehyde. But that ain't the point. The point: Benzaldehyde chlorinated gives benzoyl chloride. Is that ticking sound coming from inside your head?
Say we need something dry, say this is acetic anhydride. Dick's Practical Receipts (1872) Post 302737 (bocuse: "Nice Old Acetic Anhydride Synth", Chemistry Discourse) suggests reacting benzoyl chloride with dry (fused, powdered) sodium acetate to enable distilling off acetic anhydride. We have a door open here. This discussion continues in Post 304734 (SideArm: "Why Benzoyl Chloride", Chemistry Discourse).
(Hive Bee)
05-04-02 13:15
No 304851
Benzyl chloride.
Niki, Senji. (Japan). Japan. Kokai (1977),
JP 52111520 Patent written in Japanese.
Abstract
Cl (146 kg) was introduced into a mixt. of 330 kg PhMe and 3 kg red P over 9 h at 90-5.5° and the mixt. stirred 1 h to give 172 kg PhCH2Cl (purity 99.5%).
If the molar ratio is 1:1 then there is 20 Kg too much Cl used.
When I wanna have Benzal Chloride is the molar ratio 1:2 or not???
Say for Benzyl Chloride 330 Kg of Toluene reacting with 126,974 of Cl.
For Benzal Chloride 330 Kg of Toluene reacting with 253,95 Kg of Cl. Is this rite???
Elementary
(Hive Addict)
05-01-02 17:36
Post 303804 (Elementary: "Benzyl Chloride 2 Benzaldehyde", Chemistry Discourse)
Benzyl Chloride 2 Benzaldehyde
If the end product that you require is benzaldehyde then this can also be made from benzyl chloride :
Benzyl chloride is boiled under reflux for several hours with a solution of cupric nitrate or lead nitrate, when hydrolysis and oxidation occurs:
C6H5.CH2Cl + H2O = C6H5.CH2OH + HCl
C6H5.CH2OH + O = C6H5.CHO + H2O
A stream of carbon dioxide is usually passed through the mixture to remove oxides of nitrogen. The benzaldehyde is extracted with ether, dried with anhydrous calcium chloride, and distilled. If necessary it can be purified further by forming a crystalline addition compound with sodium bisulphite and distilling this with dilute sulphuric acid.
Please tell me more. Looks easy.
This is example 1 from Patent GB 899953 (http://l2.espacenet.com/espacenet/viewe
To 700 parts of distilled Benzal Chloride there was added 2 parts by weight of anhydrous zinc chloride and the two were mixed thoroughly with stirring while heating to 105-110°C. When the reaction mixture has reached 105-110°C addition of water begun on a slow rate while maintaining a temperature of 110-120°C. The addition of water was continued untill a total of 85 parts by weight of water had been added (approximately 5% excess) at which time the evolution of HCl ceased. Reaction temp was maintained for another hour to be sure all the HCl had been removed, and the Benzaldehyde had been removed by vacuum distillation. The yield of Benzaldehyde recovered at non-distillation 95% of theory and the purity better than 96,5%
Prep of Chlorine gas by Eleusius (../rhodium
/eleusi
You've gotta love me.