CYCLOPHANES WITH SHARP CORNERS - SYNTHESIS OF MACROCYCLES CONTAINING ONE OR 2 1,5,2,4,6,8-DITHIATETRAZOCINE RINGS

Several cyclophanes have been prepared which contain one or two of the bent 3,7-diamino-1,5,2,4,6,8-dithiatetrazocine (DTTA) ring systems li nked by polymethylene chains: 1,8-dimethyl-1,8-diaza[8](3,7)(1,5,2,4,6 dithiatetrazocinophane) (6), 1,6,1 5,20-tetramethyl-1,6,15,20-tetraaz a[6.6] (3,7)(1,5,2,4,6,8-dithiatetrazocinophane) (8), and 1,5,14,1 8-t etramethyl-1,5,14, aaza[5.5](3,7)(1,5,2,4,6,8-dithiatetrazocinophane) (9). In each synthesis, an N,N'-dimethyl-alpha,omega-diamine was conve rted to the corresponding bis(guanidinium hydrobromide), which was the n treated with sulfur dichloride in the presence of DBU under conditio ns of moderate dilution to form the cyclophane in low yield (0.1-0.7%) . When N,N'-dimethylhexanediamine was used, a cyclophane containing a single DTTA ring bridged by the polymethylene chain was formed (6), bu t with the corresponding butane- and propanediamines, dimeric cyclopha nes containing a pair of DTTA rings resulted (8 and 9). When N,N'dimet hylpentanediamine was used, a monomeric phane, ethyl-1,7-diaza[7](3,7) (1,5,2,4,6,8-dithiatetrazo- cinophane) (7), appeared to be formed, but it was not isolated as a pure material. Compounds 6, 8, and 9 were ch aracterized by X-ray crystallography. Crystallographic data: for 6, C1 0H18N6S2, monoclinic P2(1)/c, Z = 4, a = 8.356(1) Angstrom, b = 12.991 (2) Angstrom, c = 13.298(2) Angstrom, beta = 111.705(9)degrees; for 8, C16H28N12S4 . 0.69CH(2)Cl(2), triclinic, <P(1)over bar>, Z = 2, a = 9 .6095(8) Angstrom, b = 11.7085(11) Angstrom, c = 13.2683(10) Angstrom, alpha = 66.243(7)degrees, beta = 82.340(6)degrees, gamma = 73.989(7)d egrees; for 9, C14H24N12S4, triclinic <P(1)over bar>, Z = 2, a = 6.304 (1) Angstrom, b = 8.366(1) Angstrom, c = 21.357(3) Angstrom, alpha = 9 1.03(1)degrees, beta = 92.26(1)degrees, gamma = 110.56(1)degrees. The dimeric cyclophanes 8 and 9 were observed to form roughly rectangular a small cavity, with the DTTA rings at two of the comers. The DTTA rin g of the monomeric phane 6 was observed to be significantly distorted when compared with the structures of less constrained DTTA's, and ab i nitio calculations indicated that the phane 7, which has a shorter bri dge, but for which there is no X-ray structure, is even more highly st rained.