Selenocarboxylic acid salts such as alkali metal and ammonium sails are Luc must im portant starting compounds for the synthesis of selenocarboxylic acid derivatives. However, their synthesis has been lim ited to arom atic potassium [1] and piperidinium selenocarboxylates [2,3], because of the difficulties in the crystallization and purification of the aliphatic salts and of the limited availability of the starting bis(acyl) selenides. Recently we succeeded in the iso lation of a series of aliphatic bis(acyl) selenides [4], We now report the first isolation of simple potassium alkanecarboselenoates (2) and Se-alkyl alkanecarbo selenoates (3), via the bis(acyl) selenides. Results and DiscussionThe expected aliphatic potassium selenocarboxy lates (2) were isolated as crystals from the reaction of the corresponding aliphatic bis(acyl) selenides with potassium m ethanolate (eq. (1)

A series of sodium selenocarboxylates 2 were isolated from the reaction of diacyl selenides with sodium ethanolate and characterized. A convenient preparation of the sodium salts 2 by the direct reaction of acyl chlorides with sodium selenide was also established. The salts are colourless to slightly pale yellow crystals and labile towards moisture. They readily react with alkyl iodides at room temperature to give the corresponding Se‐alkyl esters 3.

Reaction between sodium 1-imidazolecarbodithioate, prepared from sodium imidazole and carbondisulfide, and α-haloketone gave the corresponding 1,3-oxathiole derivatives in high yields.

236ChemInform Abstract The first isolation of simple potassium alkanecarboselenoates (III) and Se-alkyl alkanecarboselenoates such as (V) (8 examples) via the bis(acyl)selenides (I) is reported.

Guajazulen (I) reagiert mit Malonyldichlorid (II) ohne Katalysator unter Acylierung zum Carbonsäurechlorid (III), aus dem bei einer Hydrolyse mit Wasser neben der Carbonsäure (IV) auch das Keton (V) durch Kohlendioxid‐Abspaltung gebildet wird.