How is 1,1',1'',1'''-[Disulfanediylbis(carbonothioylnitrilo)]tetrabutane (CAS: 1634-02-2) typically synthesized?

1,1',1'',1'''-[Disulfanediylbis(carbonothioylnitrilo)]tetrabutane (CAS: 1634-02-2) is typically synthesized through the reaction of butanedione tetrakis(nitrile) with sulfanediyl dichloride. The process involves the use of a base to facilitate the nucleophilic attack on the nitrile groups, followed by the formation of the disulfide bond. The reaction requires careful control of temperature and stirring to achieve high selectivity and yield.