Diethyl ether is a true ether, meaning it has the "ether linkage" R-O-R, where the "R" stands for alkyl group. In the case of Diethyl ether R = ethyl group i.e. CH3-CH2-O-CH2-CH3. Some ethers have different alkyl groups attached e.g. methylethyl ether CH3-0-CH2-CH3. Don't be tempted to go for unusual ethers, many are highly toxic and/or inflammable.
Petroleum ether is a mixture of short chain hydrocarbons, usually between pentyl and heptyl, and is sold by it's boiling point range e.g. 30-60*C.
This is not a true ether because it doesn't contain the -O- linkage.
As for classification/restriction:
Check out
Code of Practice for Supply Diversion into Illicit Drug Manufacture
Diethyl ether is a cat#3 chemical.
CATEGORY III - ILLICIT DRUG REAGENTS/ESSENTIAL CHEMICALS
No Reporting Required. This list should be used as guide to alert staff that these products
may be used in illicit drug manufacture
Be well aware that any chemical sales person worth their weight these days will smell "drugs" a mile off. However, ether is used for many things so it has legit uses.
Also remember: Ether is a dangerous chemical to have around. Besides being highly inflammable, it is very volatile and has a low boiling point, so it will escape from most bottles, even well stoppered bottles. Keeping it in the freezer or fridge is also a no no as it will still escape, and any sparks from the compressor, the light switch or other source can ignite it.
From wiki
The autoignition temperature of ether is only 170 °C (338°F), so it can be ignited by a hot surface without a flame or spark.
Compare the vapour pressure charts for
Dietheyl ether and
Ethanol
Most importantly, ether when left standing for any time can form explosive peroxides that are sensitive enough to explode from movement - or less! Various antioxidants can be added to help prevent peroxides from forming, but stay away from old bottles.
In regards to any solvent anyone is thinking of inhaling, please do your homework first before jumping in feet first, and that means looking beyond the anecdotes to some real science.
Most alcohols present some dangers although these will vary in accordance with things like alkyl chain length and branching, and whether the alcohol is primary, secondary or tertiary as this affects metabolism. So it's worth reading up well before deciding to go down this path.
ISOPROPANOL IARC
If you're dead set on trying other alcohols try looking at the threads in Advanced Drug Discussion on 2-methyl-2-butanol, and read up the MSDS and safety info - lethal dosages etc. Some are more potent than ethanol; overdose is a real possibility, and in most cases, presents the same dangers as ethanol poisoning i.e. it can kill.
