Complexation with diol host compounds. Part 14. Inclusion compounds of 2,2′-bis(9-hydroxy-9-fluorenyl)biphenyl with acetonitrile, cyclohexanone, di-n-propylamine and dimethylformamide

Abstract

The structures of the inclusion compounds of 2,2′-bis(9-hydroxy-9-fluorenyl)biphenyl (H) with acetonitrile (1) (1:1), cyclohexanone (2) (1:2), di-n-propylamine (3) (1:1) and dimethylformamide (4) (1:2) are reported. Crystal data: (1) monoclinic, P2₁/c with a=10.500(3), b=15.598(3), c=18.344(3) Å, β=96.66(2)°, Z=4, D _C=1.24 g cm⁻³. (2) monoclinic, P2₁/c with a=13.980(3), b=11.768(5), c=23.49(1) Å, β=98.77(3)°, Z=4, D_c =1.24 g cm⁻³. (3) monoclinic, C2/c with a=29.57(1), b=13.485(4), c=18.17(1) Å, β=107.94(4)°, Z=8, D _C=1.16 g cm⁻³. (4) monoclinic, C2/c with a=30.123(9), b=13.391(6), c=19.177(6) Å, β=111.23(4)°, Z=8, D _C=1.22 g cm⁻³. Final R values for the four structures were 0.065, 0.120, 0.084 and 0.107 for 2937, 2830, 2071 and 3769 reflections, respectively. The host conformation is quite rigid and does not appear to be influenced by the shape and size of the guests studied. The host is held in a spiral conformation by means of an intramolecular hydrogen bond. In addition, host-guest hydrogen bonds are observed in all structures. Thermal analysis was used to evaluate the strength of binding of the guest molecules and confirmed that (1) is the most stable of the four compounds studied.