Über Chalkogenolate. LIII. Untersuchungen über Thioameisensäuren 1. Darstellung und Eigenschaften von Monothioformiaten und Monothioameisensäure

Na[HCOS] or [KHCOS] were prepared by hydrolysis of phenyl formate with NaHS or KHS. The monomeric monothioformic acid is formed on treatment of Na[HCOS] with 18% HCl and it can be distilled from the solution in a vakuum at ?5°C. The pale yellowish acid exists in the thiol form HCOSH and polymerizes even at 30°C. The S-methyl ester HCO(SCH₃) is formed on reaction of Na[HCOS] with methyl iodide, and the O-methyl ester HCS(OCH₃) on reaction of methyl orthoformate and H₂S in the presence of ZnCl₂ and hydroquinone. The prepared compounds were characterised by different methods.