PREPARATION OF 1,2,3-NAPHTHALENETRIAMINE, 1,2,5,6-NAPHTHALENETETRAMINE AND 1,2,7,8-NAPHTHALENETETRAMINE, AND 5,6,7,8-QUINOLINETETRAMINE AND 5,6,7,8-ISOQUINOLINETETRAMINE BY REDUCTION OF THE FUSED 1,2,5-THIADIAZOLE RING

The two fused 1,2,5-thiadiazole-rings of naphthalenes 1a and 1b, quinoline 2a, and isoquinoline 2b were reduced with tin and concentrated hydrochloric acid in refluxing dioxane, giving the expected 1,2,5,6-naphthalenetetramine (4a) and 1,2,7,8-tetramine derivative 4b, 5,6,7,8-quinolinetetramine (15a) and isoquinoline analogue 15b in moderate yields. Partially reduced diamine 5 was formed as a by-product in the reduction of 1a. The expected 1,2,3,4-naphthalenetetramine (4c) was not obtained in the reduction of 1c at room temperature and the 1,2,3-triamine 8 was formed in 27% yield. The intermediary formation of 4c was confirmed by acetylating the crude reduction mixture of 1c, giving tetraacetyl derivative 11. The reduction of naphthotris[1,2,5]thiadiazole 3 afforded 4,5-diamine 16 in 44% yield. Polyamines 4a-b, 8, 15a-b, and 16, were obtained as their hydrochloride(s).