D-limonene from oranges

Limonene, aka 4-isopropenyl-1-methylcyclohexene or dipentene, is a colourless or slightly yellow liquid. Naturally it occurs in many citrus fruits. It's the chemical that gives citrus rinds their wonderful smell.

I had a go at extracting it from orange peel via steam distillation. I started with five oranges and grated all the rinds of them. Next I placed the rinds into a round bottom flask with 150ml water and set up for simple distillation. I kept the distillation going until around 10ml of liquid was left in the round bottom. Once the distillation was complete I transferred the distillate to a graduated cylinder and noticed an oily top layer, which smelled strongly of citrus. Limonene is a nonpolar hydrocarbon so it doesn't mix with water.

I used a pipette to extract the top limonene layer. This was my final product:

 

Hydrazine dihydrochloride

A few days ago I had a go at making hydrazine dihydrochloride. Hydrazine dihydrochloride is a salt of hydrazine with the formula N2H2.(HCl)2. It's a white crystalline solid used as a convenient source of freebase hydrazine in organic chemistry. It is present in some soldering fluxes. I plan to use mine for making azides.

To make it I started by adding 250ml of chilled 5%ish sodium hypochlorite solution to a 1 litre beaker. I then dissolved 16 grams of sodium hydroxide slowly into the hypochlorite solution (to insure the reaction environment is alkaline). In a new beaker I prepared a solution of 0.375 grams of gelatine (the role off the gelatin is unkown) and 11 grams of urea in around 40 millilitres of water. I then quickly added all of the gelatine/urea solution to the hypochlorite hydroxide solution and started stirring with vigour. A bit of foaming was observed (probably due to partial product decomposition to nitrogen). The reaction mixture was then heated up to 85-90 C for 6 minutes to form the hydrazine. Next it was chilled close to 0 C and then 117 millilitres of 33% hydrochloric acid was added slowly with brief gentle stirring at each addition. The hydrazine must be neutralised twice: first to make hydrazine monohydrochloride, which is very soluble, and next to make hydrazine dihydrochloride, which will partially precipitate.

After a few minutes, crystals of hydrazine dihydrochloride were observed precipitating. These were collected via filtration, and dried. The product is shown below:

Overall this worked terribly, requiring TWICE as much acid as would have been used forming hydrazine sulphate. The yields were horrible. Next time I do this I'll use sulphuric acid at the end, and make hydrazine sulphate.

Methylamine hydrochloride

Methylammonium chloride aka methanamine hydrochloride, methylamine hydrochloride or just aminomethane hydrochloride, is an interesting compound with the formula CH5N.HCl. I plan to use my sample to make methyldichloramine and possibly N-methyl-2-propanimine. This is how I made it:

I started by pouring some powdered hexamethylenetetramine into a 1L flask. I then poured an excess of dilute hydrochloric acid and quickly corked the flask. I shook the flask and noticed a lot of fumes and white smoke being produced in the flask. Once the smoke had redissolved I saw that all the hexamethylenetetramine had dissolved. I left the corked flask to stand overnight and in the morning I noticed there was a crystalline precipitate of ammonium chloride in it. I transferred the mixture to a round bottom flask and setup for reflux. After the mixture had been refluxing for about 4 minutes I noticed the ammonium chloride redissolved. In total I refluxed the mixture for about 2 hours and after this I noticed it was slightly yellow (this is due to a dimethylamine impurity).

Next I started boiling down the mix and as soon as lots of crystals of methylamine hydrochloride and ammonium chloride started precipitating I turned off the heat. I filtered out the crystals and quickly dried them. Next I added boiling ethanol to the crystals.

Methylamine hydrochloride is very soluble in ethanol whereas ammonium chloride is rather insoluble. I filtered again discarded the insoluble ammonium chloride. As for the filtrate solution of the product, I boiled it down in a water a water bath until I was left with small white crystals of methylamine hydrochloride. I repeated this process (boiling down the mixture, filtering the crystals, adding boiling ethanol etc. until the reaction mixture was consumed. I noticed sometimes my product was yellow. I just washed the yellowness out with very cold ethanol and I was left with a relatively pure product:

Dichloromethane from paint stripper

Dichloromethane, also called methylene chloride or simply DCM, is an extremely useful organic solvent with the formula CH2Cl2. It's a very volatile colourless liquid with a heavy sweetish smell, similar to chloroform.

I'm in urgent need of it and I can't find anywhere to buy it cheaply so I thought I'd try extracting it from paint stripper. I purchased 500ml of "Selleys kwik strip". According to the material safety data sheet (MSDS) the stripper contains:

>60% dichloromethane
10-<30% ethanol
1-<10% light aromatic petroleum
1-<5% aqueous ammonia
And "additives" to 100% (presumably cellulose-derived gelling agents)

I poured 250ml of the "kwik strip" into a large round-bottom flask and setup for distillation. I kept the distillation temperature around 60 C and after no more product came over, I stopped the distillation.
I believed the distillate contained mostly ethanol and dichloromethane, so I washed it with twice its volume of water to remove the ethanol. I was left with a nice amount of usable dichloromethane.

Sulphovinic acid

I made this chemical last weekend. It's interesting stuff. I plan to use it to make sodium ethylsulphate and eventually diethyl thioether.

Here's some information about it: sulphovinic acid, also known as ethoxysulphonic acid, ethyl bisulphate, ethylsulphuric acid or simply ethyl sulphate is an acid with the formula C2H6SO4. It exists as a colourless liquid at room temperature and pressure.

This is how I made it:

I started by adding some ethanol and twice as much sodium bisulphate by molar mass to a large round bottom flask. I then refluxed this mixture for an hour after which not much had changed.

I decided this was due to poor mixing of the reactants. To combat this I refluxed the mix for another hour while shaking the appuratus to keep the sodium bisulphate in a suspension in the ethanol. About 30 minutes into this I noticed a fine precipitate of presumably sodium sulphate forming.


It's important that the reflux temperature does not exceed 140 C as this will favor the formation of diethyl ether over sulphovinic acid.

As soon as I noticed that no more sodium sulphate was forming, I plunged the round bottom flask containing the reaction mix into an ice bath. This allows the sodium sulphate to form a hydrate with the water produced in the reaction. This is an important step as the sulphovinic acid produced in the reaction decomposes on contact with water. Anyway, I then filtered the mixture to remove the sodium sulphate decahydrate precipitate and I was left with clear liquid (presumablely sulphovinic acid).

I haven't had a chance to test the sulphovinic acid yet. I'll post once i've tested it.

2 NaHSO4 + C2H5OH ==> C2H6SO4 + 2 NaSO4 + H2O

Sulphur monochloride synthesis

SULPHUR MONOCHLORIDE

I've been planning this experiment for a while now and I've finally had a chance to try it out: making sulphur monochloride at home.

Sulphur monochloride, also known as disulphur dichloride, is an interesting chemical with the formula S2Cl2. It exists as a golden yellow liquid with a high boiling point around 137 C. It's used in the industrial setting to produce various sulphur dyes and insecticides. It reacts violently with water.
I'm interested in it because of its reaction with hunigs base.

SYNTHESIS                              

WARNING: Sulphur monochloride causes severe chemical burns and chlorine gas can KILL you. Attempt at your own risk.


ATTEMPT ONE
For my first attempt I got a flask and filled it with sulphur, then I used some tubing to connect it to another flask, which I used as my chlorine generator. My plan was to get the chlorine into the flask of sulphur then heat it with a torch to kick start the reaction.
                   
For my chlorine generator I used sodium dichloroisocyanurate and dilute hydrochloric acid and anhydrous calcium chloride to dry the chlorine. Due to the heaviness of the chlorine I only managed to get a small amount of chlorine into the flask so I only obtained a small amount of sulphur monochloride shown here:

I'll try again soon with a better chlorine generation system and see If I can get more product forming.