Synthesis and electrode properties of 19-membered azo- and azoxycrown ethers. Structure of dibenzo-19-azocrown-7

Photochemical Rearrangement of a 19‐Membered Azoxybenzocrown: Products and their Properties

“…The 19‐membered p ‐hydroxyazobenzocrown 19‐ p ‐OH was now obtained in a reaction analogous to the Wallach rearrangement (Scheme ). The procedure was similar to that described earlier for 13‐ and 16‐membered hydroxyazobenzocrowns, using the 19‐membered azoxybenzocrown 19‐AZB‐O . In this way, under optimized conditions, 19‐ p ‐OH was obtained with the highest, among all prepared until now hydroxyazobenzocrowns, yield of 82 %.…”

“…I. In a two‐neck round‐bottom flask acetone (110 mL), microgranules of NaOH (29.8 g, 0.745 mol) and 1,11‐bis(2‐nitrophenoxy)‐3,6,9‐trioxaundecane, podand P‐5O−NO2 , (11.53 g, 0.026 mol) are placed. To the vigorously stirred mixture a suspension of stannous chloride dihydrate (29.8 g, 0.157 mol) in water (90 mL) was added dropwise over 20 min.…”

“…The pure product (1.3 g) crystallizes from 2‐propanol; mp: 85–87 °C. ( – an oily product was obtained).…”

Synthesis and structures of transition metal pacman complexes of heteroditopic Schiff-base pyrrole macrocycles

“…Deuterated solvents were dried (C 6 D 6 and C 5 D 5 N over potassium, CDCl 3 was stirred over activated alumina), trap-to-trap vacuum distilled, and freeze-pump-thaw degassed three times prior to use. Syntheses of VCl 3 (THF) 3 and TiCl 3 (THF) 3 , 51 5,5'-diformyldiethyl-2,2'dipyrromethane 2a and 9,9-Bis(5-formylpyrrole-2-yl)fluorene 2b, 23 2,2'-dichloro-N-methyldiethylamine, 52 and tetraethyleneglycolbis(o-nitrophenylether), 53 were carried out as described in the literature. Pyrrole was distilled under reduced pressure prior to use, and all other chemicals were used as purchased.…”

Molecular structures of two E-azobenzocrown ethers

“…In the larger 19-membered azobenzocrown or 20-membered azobenzoazoxybenzocrown the dihedral angles between the benzene residues of the azo-and azoxybenzene moieties are in the range 70-80° [16,17]. Both in 1A and 1B the conformation of the part of the macrocycle between C(5)-C(6)-O(7) and C(13) is described by the same sequence of torsion angles: g(gauche), a(anti), a, c(cis), c, a, a, c starting at the C(5)-C(6) bond ( Table 2).…”