2,2-Bis(3-chloromethyl-4-ethoxyphenyl)propane

The title compound, C21H26Cl2O2, a bis-chloromethyl derivative of O-ethylated bisphenol A, exhibits C 2 molecular symmetry. It shows a bent conformation with the two benzene rings nearly perpendicular [dihedral angle = 87.17 (6)°].

The title compound, C 21 H 26 Cl 2 O 2 , a bis-chloromethyl derivative of O-ethylated bisphenol A, exhibits C 2 molecular symmetry. It shows a bent conformation with the two benzene rings nearly perpendicular [dihedral angle = 87.17 (6) ].

Related literature
For more information on the synthesis, see: Miyazawa et al. (1999). For background to the investigation of new conjugated polymers derived from bisphenols as potential organic semiconducting materials, see: Jaballah et al. (2006). For the use of bis-chloromethyl bisphenol A ethers for the control of fungal and bacterial organisms, see: Priddy & Hennis (1970

2,2-Bis(3-chloromethyl-4-ethoxyphenyl)propane
Nejmeddine Jaballah, Taha Guerfel and Mustapha Majdoub S1. Comment BPAEtCl was synthesized as part of an ongoing program on the investigation of new conjugated polymers derived from bisphenols as potential organic semi-conducting materials (Jaballah et al., 2006). This intermediate is of value in synthetic work inasmuch as the CH 2 C1 group can be converted to other groups such as CH 2 CN, CH 2 OH and CHO.
Particularly, the bend-like structure of bisphenol A (BPA) nucleus offers a special interest in metacyclophanes synthesis (Miyazawa et al., 1999). Bis-chloromethyl bisphenol A ethers are also useful as microbicides for control of fungal and bacterial organisms (Priddy & Hennis, 1970). The molecular structure of BPAEtCl is shown in Fig

S2. Experimental
BPAEtCl was synthesized in two steps from 4,4′-isopropylidenediphenol [Bisphenol A, BPA]. To a stirred mixture of BPA (10 mmoles) and K 2 CO 3 (40 mmoles) in 20 mL of dimethylformamide, was added dropwise bromoethane (30 mmoles). After stirring for 5 h at room temperature, the reaction mixture was poured into distilled water and extracted with diethyl ether. The extract was washed with distilled water, dried over anhydrous MgSO 4 , and then evaporated. The resultant crude product was purified by recrystallization from ethanol/water (3/1) to afford the 2,2-bis-(4-ethoxyphenyl)propane [BPAEt] as needle-like white crystals. A mixture of BPAEt (10 mmoles), paraformaldehyde (2.5 g), and 37% aqueous HCl (8.5 mL) in acetic acid (30 mL) was heated at 328 K for 5 h. The resulting mixture was then poured into distilled water and extracted with diethyl ether. The organic layer was washed several times with distilled water and dried over anhydrous MgSO 4 . After solvent removal and two recrystallizations from hexane, we obtained BPAEtCl as colourless crystals. Yield: 75%; mp: 352-354 K.

S3. Refinement
Hydrogen atoms were located in a fourier map and refined freely with isotropic thermal parameters.  The molecular structure of BPAEtCl, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms have been omitted. Symmetry code: (i) -x + 1, y, -z + 5/2. Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.