Sodium—continued hydrosulphite

A greater measure of continuity is achieved in the Pad-steam process in which the cloth is first pigment-padded, dried, padded with sodium hydroxide and hydrosulphite, passed through a steam chamber to reduce and fix the vat dye, and finally finished off in a soaping and rinsing range. 

Decomposition of (72) in ethanolic sodium hydrosulphite generates, in situ, an azine which fragments to give nitrogen and cyclo-octatetraene. The yield of cyclo-octatetraene is substantially lower than the yield of cyclo-octadiene from (73). The controversy concerning the origin of this result continues. Anastassiou has re-affirmed the view that there is symmetry-controlled opposition to a linear cheletropic process in (72) but not in (73). 

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