Poly(carbonates) and Poly(thiocarbonates)
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Diphenols
The diphenols bis(4-hydroxyphenyl)-dimethylsilane, bis(4-hydroxy-
phenyl)-ethylmethylsilane, and bis(4-hydroxyphenyl)-diethylsilane,
were synthesized from p-bromo-phenol and dimethyl-, ethylmethyl-
or diethyl-dichlorosilane, according to the procedure described by
Davidson et al.,9 in which 14.1 g (0.08 mol) of p-bromophenol in THF
were added under N2 to 75 mL of n-butyllithium (2.5 N solution in n-
hexane) at –70◦C. Then, the temperature was increased slowly until 5◦C
and the mixture was stirred for 1 h. The temperature was decreased to –
50◦C and 0.025 mol of dimethyl-, ethylmethyl-, or diethyl-dichlorosilane
were added in THF, and the temperature increased until 10◦C and was
stirred for 2 h. The mixture was hydrolyzed by adding 5% HCl until
obtaining a yellow mixture (pH 1). The organic layer was dried under
MgSO4 and the solvent evaporated. The brown oil was poured into n-
hexane obtaining a white solid, which was recrystallized from toluene
and characterized.
Bis(4-hydroxyphenyl)-dimethylsilane: m.p: 170–171◦C (Lit.8 173–
174◦C). I.R. (KBr) (cm−1): 3319 (OH), 3020 (H arom.), 2958, 2871 (CH3),
1598, 1500 (C C arom.), 1457 (CH3), 829 (arom. p-subst.). 1H NMR (δ)
(ppm) (acetone-d6) 0.45 (s, 6H, CH3), 6.84 (d, 4H, arom), 7.35 (d, 4H,
arom), 8.41 (s, 2H, OH). 13C NMR (δ) (ppm) (acetone-d6): −1.36 (CH3-Si),
116.2, 129.2, 136.8, 159.6 (arom.) 29Si NMR (δ) (ppm) (CDCl3): −9.36.
Bis(4-hydroxyphenyl)-ethylmethylsilane: m.p.: 138–140 ◦C. I.R.
(KBr) (cm−1): 3314 (OH), 3026 (H arom.), 2954, 2874 (CH3), 2912 (CH2),
1600, 1503 (C C arom.), 1459 (CH3), 831 (arom. p-subst.). 1H NMR (δ)
(ppm) (acetone-d6): 0.51 (s, 3H, CH3-Si), 1.47 (m, 5H, CH2-CH3), 6.92
(d, 4H, arom.), 7.42 (d, 4H, arom.), 8.47 (s, 2H, OH). 13C NMR (δ) (ppm)
(acetone-d6): -4.00 (Si-CH3), 7.40 (CH2-CH3), 8.25 (CH2-CH3), 116.3,
128, 137.1, 159.6 (C arom.). 29Si NMR (δ) (ppm) (CDCl3): -6.93.
Bis(4-hydroxyphenyl)-diethylsilane: m.p.: 77–78◦C. I.R. (KBr)
(cm−1): 3330 (OH), 3055 (H arom.), 2960, 2878 (CH3), 2935 (CH2), 1599,
1502 (C C arom.), 1456 (CH3), 821 (arom. p-subst.). 1H NMR (δ) (ppm)
(CDCl3): 0.97–1.03 (m, 10H, CH2-CH3), 4.64 (s, 2H, OH), 6.84 (d, 4H,
arom.), 7.38 (d, 4H, arom.). 13C NMR (δ) (ppm) (CDCl3): 4.23 (CH3), 7.42
(CH2), 114.9, 127.6, 136.6, 156.4 (C arom.). 29Si NMR (δ) (ppm) (CDCl3):
−4.83.
Poly(carbonates) and Poly(thiocarbonates)
The poly(carbonates) and poly(thiocarbonates) were synthesized ac-
cording to the following general procedure: the diphenol (1 mmol) was
dissolved in 0.5 M NaOH and water (total volume 15 mL), and then