Reading a book on carbonate esters, in particular interested in synthesis of certain specific ones, which can be done in a couple of highly specific cases, without using phosgene to prepare them, something I absolutely WILL NOT use under any circumstances because it is a truly lethally potent, deadly toxic gas, with little warning properties and which once exposed to it, if one is exposed to even a very small quantity, there is no healing to be done, no treatment, no cure. You die. About 2 parts per million in air is enough to absorb a lethal dose almost immediately to straight away within a breath or two at most.
But a handful, just two or three of these useful alkylating agents of low toxicity and useful solvents can be prepared using alkylene epoxides, such as ethylene and propylene oxide, and from these, other esters can be made using transesterification techniques which allows the ones that are usually made with phosgene to be made from the ones which can use epoxide ring-opening techniques instead.
Because some of these carbonate esters, such as dimethyl carbonate, for example are alkylating agents, but which unlike 'traditional' commoner alkylating agents are both greatly less in toxicity than things like dimethyl sulfate, diethyl sulfate, even methyl iodide, and certainly less dangerous than the likes of methyl fluorosulfonate 'magic methyl', an EXTREMELY powerful and highly toxic superelectrophilic methylating agent, banned in most research labs due to toxicity, and diazomethane, another very effective methylating agent, being more or less a methyl carbocation precursor trapped as a diazo compound, which is highly unstable (indeed, extremely explosive and very sensitive, needing special diazomethane glassware kits for generation and use of it, a yellow, very poisonous gas which can explode from as little as contact of the gas with a sharp edge (think a pipette-tip, if it hasn't been specially flame-polished before use, or the ground glass joints of glassware, even a hairline crack in a small region of the glassware anywhere, can cause it to detonate, and it is as toxic, easily, as phosgene, and also a carcinogen). It decomposes on use, the diazonium group breaking down and leaving as the extremely stable and inert elemental, gaseous N2 (nitrogen gas) and delivering a free methyl carbocation.
https://en.wikipedia.org/wiki/DiazomethaneDiazomethane, aka diazirine needs using in a fume hood, by a chemist in full protective personal equipment and who is aware and knows what they are doing handling it, special glassware setup and the fume hood behind a blast-shield. I wouldn't dream of using it. I don't have any confidence in my ability to survive the experience.
But dimethyl carbonate isn't just vastly less toxic than almost all methylating or other alkylating agents, its even green and environmentally friendly. Just needs phosgene to make it. But ethylene carbonate, or propylene carbonate don't need (Cl2)C)=O and could AFAIK be transesterified with methanol to make it.
Useful solvent too, same for propylene/ethylene carbonates. Plenty of things I could do with those, and other hobby chemists would be as delighted to be able to obtain it as I would. Which means if I do, the hobbyist community can be made aware of the fact and then come to ol' uncle Lestat for their carbonate ester needs and desires. Do have other things to do of course, but if I can get that synthesis from ethylene and propylene oxides and transesterification with MeOH to work, then I think it would be quite popular. On ebay too, I KNOW it would get snapped up on ebay by people with minds who function on the same wavelengths I do.
Hell, if I found any on ebay I'd grab it.
So I've been studying that book on the carbonate esters; found it online.