5,7,13,15-Tetra­oxo-2,2,10,10-tetra­kis­(trifluoro­meth­yl)-4,8,12,16-tetra­oxa-1(1,4),3(1,4),6(1,2),9(1,4),11(1,4),14(1,2)-hexa­benzenahexa­deca­phane tetra­hydro­furan monosolvate

Qing-Zhong Guo; Yi Du

doi:10.1107/S1600536812011166

. 2012 Mar 21;68(Pt 4):o1126. doi: 10.1107/S1600536812011166

5,7,13,15-Tetraoxo-2,2,10,10-tetrakis(trifluoromethyl)-4,8,12,16-tetraoxa-1(1,4),3(1,4),6(1,2),9(1,4),11(1,4),14(1,2)-hexabenzenahexadecaphane tetrahydrofuran monosolvate

Qing-Zhong Guo ^a,^*, Yi Du ^a

PMCID: PMC3344072 PMID: 22589981

Abstract

The title compound, C₄₆H₂₄F₁₂O₈·C₄H₈O, consists of a cyclic aryl ester dimer and a tetrahydrofuran molecule. In the structure of the cyclic dimer, one carbonyl group stretches above the cavity and the other below.

Related literature

For related structures of the cyclic aryl ester dimer, cyclo-bis[1,4-phenylene(hexafluoroisopropylidene)phthalate] tetrahydrofuran monosolvent, see: Jiang et al. (1997b ▶); Teasley et al. (1998 ▶); Qi et al. (1999 ▶); Guo et al. (2003 ▶). For the use of ring-opening polymerization (ROP) reactions of cyclic aryl oligomers in the preparation of high performance aromatic polymers, see: Brunelle (2008 ▶); Brunelle et al. (1990 ▶); Chan et al. (1995 ▶); Jiang et al. (1997a ▶). For ideal bond angles, see: Coulter & Windle (1989 ▶);

Experimental

Crystal data

C₄₆H₂₄F₁₂O₈·C₄H₈O
M _r = 1004.76
Triclinic,
a = 9.3857 (17) Å
b = 11.2748 (17) Å
c = 12.615 (2) Å
α = 105.715 (14)°
β = 97.969 (14)°
γ = 103.167 (14)°
V = 1222.4 (3) Å³
Z = 1
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 293 K
0.43 × 0.33 × 0.30 mm

Data collection

Siemens P4 diffractometer
Absorption correction: ψ scan (XSCANS; Bruker, 2001 ▶) T _min = 0.950, T _max = 0.964
5660 measured reflections
4684 independent reflections
1916 reflections with I > 2σ(I)
R _int = 0.022
3 standard reflections every 197 reflections intensity decay: 2.2%

Refinement

R[F ² > 2σ(F ²)] = 0.065
wR(F ²) = 0.158
S = 1.00
4684 reflections
344 parameters
H-atom parameters constrained
Δρ_max = 0.32 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Data collection: XSCANS (Bruker, 2001 ▶); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812011166/zj2060sup1.cif

e-68-o1126-sup1.cif^{(20.5KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812011166/zj2060Isup2.hkl

e-68-o1126-Isup2.hkl^{(229.4KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

This work was supported by grants from the National Natural Science Foundation of China (NSFC 20904045) and the Natural Science Foundation of Hubei Province (No. 2009CDB355).

supplementary crystallographic information

Comment

Ring-opening polymerization (ROP) reactions constitute an important class of polymerization reactions. The advantages of using ROP of cyclic aryl oligomers to prepare high performance aromatic thermoplastics, such as polycarbonate and poly(aryl ester)s, have been widely recognized in recent years (Brunelle et al., 1990; Brunelle, 2008; Chan et al., 1995; Jiang et al. 1997a). It is generally believed that the ROP of aromatic cyclic oligomers is essentially thermoneutral and driven by entropy changes as the cyclic oligomers have big size with little or no ring strain. In order to obtain decisive evidence of the macrocyclic structure and investigate the nature of ROP, the single-crystal X-ray structure of cyclic ester dimer, the title compound, was determined.

The structure of cyclic dimer, cyclo-Bis[1,4-phenylene(hexafluoroisopropylidene)-phthalate (shown in Fig. 1) exhibits two types of conformation about ester groups. One of the carbonyl groups stretch above the cavity of the cyclic structure and the others stretch beneath the cavity. The interplanar dihedral angle of the phenyls attached to the hexafluoroisopropylidene is 69.67°. The distance between C(14) and its symmetrical carbon atom is 1.0729 nm. The bond angles at C7—O1—C8 of 119.6° and O3—C23(O4)—C6ⁱ of 111.0° are all close to the idealized values of 118. 8° and 111.7°, respectively (Jiang et al., 1997b; Coulter & Windle, 1989). The phenyl rings in cyclic dimer have a good planarity (root mean square deviations from the planarity of the phenyl planes are 0.00043, 0.00069 and 0.00053 nm, respectively). Overall, X-ray analysis indicates that the cyclic dimer is constructed without severe internal strain. This result indicates that the ROP of cyclic aryl ester dimer is driven by entropy changes and provides a base for the study on the mechanism of ROP reaction and the relationship between the cyclic nature and ROP reaction.

Experimental

The cyclization reaction was conducted in a 500 ml threeneck round-bottom flask charged with 150 ml dichloromethane, 30 ml distilled water and 0.16 g cetyltrimethylammonium bromide at room temperature. A solution of phthaloyl dichloride (1.014 g, 5 mmol) in 50 ml dichloromethane and a solution of disodium salt of 4,4'-(hexafluoroisopropylidene) diphenol (1.682 g, 5 mmol) in 50 ml distilled water were delivered into the mechanically stirred flask in an equimolar fashion over an 8 h period. After the addition, the mixture was stirred for another 2 h to ensure complete reaction. The organic phase was separated by a separating funnel and extracted with distilled water three times and then evaporated to dryness. The colorless cyclic dimer was obtained by recrystallization from tetrahydrofuran (THF). The isolated yield of cyclic dimer was 1.3 g (54.7% yield). Colorless block crystals suitable for X-ray analysis were obtained by slow evaporation from a THF solution at room temperature for about one week.