Author Topic: Benzal Chloride ==> Benzaldehyde  (Read 3768 times)

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dickdastardly

  • Guest
Benzal Chloride ==> Benzaldehyde
« on: December 17, 2001, 11:10:00 PM »
Just found some work on creating Benzaldehyde from Benzal  Chloride just wondering if anyone had any full workups on the subject. I know that You can get Benzal Chloride from
heating toluene with an excess of Calcium hypochlorite to get benzal chloride and benzal trichloride

Rhodium

  • Guest
Re: Benzal Chloride ==> Benzaldehyde
« Reply #1 on: December 17, 2001, 11:23:00 PM »
Just heat benzal chloride in 4x its volume of dilute (10-20%) NaOH solution with good stirring, and it will hydrolyze to benzaldehyde. Extract the organic layer, distill off the solvent and then distill the benzaldehyde, preferably under vacuum.

dickdastardly

  • Guest
Re: Benzal Chloride ==> Benzaldehyde
« Reply #2 on: December 19, 2001, 11:52:00 AM »
Well I guess that sounds reasonable enough. I'm still left with one Question. What would be the correct ratio of toluene and Calcium Hypochlorite to get Benzal Chloride. I know that equal amounts make BenzYl Chloride not BenzAl Chloride

PrimoPyro

  • Guest
Re: Benzal Chloride ==> Benzaldehyde
« Reply #3 on: December 19, 2001, 12:02:00 PM »
PhCH3 (toluene) + Ca(OCl)2 --> PhCHCl2 (benzal chloride) + Ca(OH)2

1 mole toluene per mole hypochlorite in this reaction.

Toluene = 92.141 grams per mole.
Calcium Hypochlorite = 142.982 grams per mole.

So that's 155.177 grams Calcium Hypochlorite per 100 grams of Toluene.

If your toluene is pure, then that's 86.7mL Toluene per 155.177 grams Calcium Hypochlorite.

Man, you're lucky I don't sleep.  ;)

                                                 PrimoPyro

Vivent Longtemps la Ruche!

Osmium

  • Guest
Re: Benzal Chloride ==> Benzaldehyde
« Reply #4 on: December 19, 2001, 12:25:00 PM »
Heh! Toluene floats! So 100g toluene will be more than 100ml!

PrimoPyro

  • Guest
Re: Benzal Chloride ==> Benzaldehyde
« Reply #5 on: December 19, 2001, 12:43:00 PM »
Son of a bitch, I guess I need to sleep, don't I? multiplied when I shoulda divided. That's a fatique error. Sleep time now. 11:45 hours today....not as much as yesterday, heh Os? Maybe I'm losing it? We'll see tomorrow.

115.34mL toluene per 155.177g calcium hypochlorite

                                                  PrimoPyro

too tired to clean that last equation up to 100mL. Gnight....

Vivent Longtemps la Ruche!

dickdastardly

  • Guest
Re: Benzal Chloride ==> Benzaldehyde
« Reply #6 on: December 19, 2001, 06:29:00 PM »
All I can say on that one Primo P is WHOA. I was just thinking the same shit when I posted my last reply