Deaths from diazomethane poisoning have been reported. Its behavior is akin to the less convenient reagent diazomethane. NMU is the traditional precursor in the synthesis of diazomethane. Cycloheptanone is also prepared by ring expansion of cyclohexanone with diazomethane as the methylene source. The reaction mechanism was confirmed by a reaction using C-labeled diazomethane. It also reacts with alcohols to give methyl ethers, where diazomethane may not. Modifications involving cheaper alternatives have been developed, such as dibromomethane or diazomethane and zinc iodide. In contrast, most diazoalkanes without electron-withdrawing substituents, including diazomethane itself, are explosive. Inhalation of diazomethane is known to cause pulmonary edema; trimethylsilyldiazomethane is suspected to behave similarly. To generate an alkylidene carbene a ketone can be exposed to trimethylsilyl diazomethane. Specialized kits to prepare diazomethane with flame-polished joints are commercially available. The gas-phase concentration of diazomethane can be determined using photoacoustic spectroscopy. It is a less explosive alternative to diazomethane for the methylation of carboxylic acids. An alternative to the Bingel reaction is a fullerene diazomethane reaction. The stable compound cyanamide, whose minor tautomer is carbodiimide, is an isomer of diazomethane.