J Chem Crystallogr (2009) 39:399–406
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3.93–3.96 (d, 1H, J = 11.1 Hz); 6.82–6.84 (m, 2H); 6.92–
7.18 (m, 13H). The overall yield was 76.9 g (93%).
Because it is known [3], that the higher melting diaste-
reomer of 1,2,3-triphenylbutyric acid gives better yields
during cyclization to tetralone, the lower melting diaste-
reomer (28 g) was equilibrated to the 1/1 mixture (as
determined by NMR) of both diastereomers by refluxing
with potassium hydroxide in ethylene glycol and working
up as described above. After fractional crystallization as
described above 10 g of the lower melting diastereomer
was obtained along with 14 g of the higher melting isomer.
10.7 g (67 mmol) of bromine in 100 mL of glacial acetic
acid. The reaction mixture was stirred at room temperature
for 24 h, poured into 4 L of water and extracted with
dichloromethane (5 9 300 mL). The organic phase was
washed with 10% sodium bisulfite solution (500 mL), water
(4 9 500 mL), dried with sodium sulfate and the solvent
was removed on a rotary evaporator. The residue was dis-
solved into 100 mL of hot cyclohexane and left to
crystallize overnight. The crystals were filtered, washed
sparingly with cold cyclohexane and air-dried. Yield:
15.3 g (85%), m.p. 115–117 °C. 1H NMR (300 MHz,
CDCl3) d 3.10–3.17 (dd, 1H, J = 3.6 Hz and 16.8 Hz);
3.54–3.60 (dd, 1H, J = 3.6 Hz and 11.7 Hz); 3.78–3.88
(dd, 1H, J = 11.7 Hz and 16.8 Hz); 6.89–6.92 (m, 2H);
7.08–7.21 (m, 8H); 7.33–7.35 (d, 1H, J = 7.5 Hz); 7.42–
7.47 (t, 1H, J = 7.5 Hz); 7.56–7.61 (td, 1H, J = 1.5 Hz and
7.5 Hz); 8.28–8.30 (dd, 1H, J = 1.2 Hz and 7.8 Hz). 13C
NMR (75 MHz, CDCl3) d 27.1; 34.8; 54.4; 127.6; 127.7;
127.8; 127.9; 128.0; 129.0; 129.4; 129.5; 129.9; 130.3;
134.3; 138.2; 138.3; 142.5; 191.3.
Trans-2,3-diphenyltetralone
To a solution of 50.0 g (0.16 mol) of 1,2,3-triphenylbutyric
acid (the 95% pure higher melting diastereomer with 5% of
the low melting one) in 1,200 mL of benzene was added
35.9 g (0.17 mol) of phosphorus pentachloride and the
reaction mixture refluxed for 2 h. Vigorous evolution of HCl
gas was observed. After 2 h 43.6 g (0.16 mol) of stannic
tetrachloride was added. The reaction mixture was refluxed
overnight, poured into mixture of 4 L of ice cold water and
300 mL of concentrated HCl, stirred for 30 min and
extracted with dichloromethane (5 9 200 mL). The organic
phase was washed with 5% aqueous potassium hydroxide
(3 9 300 mL) and water (4 9 300 mL). The aqueous and
alkaline washings were combined, acidified and again
extracted with dichloromethane (2 9 100 mL). The organic
phase was washed with water (3 9 100 mL) and combined
with the main organic phase which was then dried with
sodium sulfate and the solvent was removed on a rotary
evaporator. The residue was dissolved in 1,400 mL of
boiling ethanol and then 800 mL removed by distillation.
Crystals formed after 48 h and were filtered and washed with
cold ethanol. Yield: 25.5 g, m.p. 148–151 °C. The combined
mother liquors were refluxed, and then ethanol was again
distilled leaving a final volume of 150 mL. This solution was
seeded with a crystal of product and left to crystallize
overnight. The crystals were filtered and washed with cold
ethanol. The second crop was weighing 5.05 g, m.p. 148–
150 °C (lit3 m.p. 143–147 °C). Total yield: 30.55 g (65%).
1H NMR (300 MHz, CDCl3) d 3.20–3.27. (dd, 1H,
J = 4.2 Hz and 16.3 Hz); 3.40–3.48 (dd, 1H, J = 11.4 Hz
and 16.3 Hz); 3.67–3.76 (td, 1H, J = 4.2 Hz and 11.8 Hz);
3.99–4.03 (d, 1H, J = 12.0 Hz); 6.96–7.00 (m, 2H); 7.01–
7.21 (m, 8H); 7.28–7.30 (d, 1H, J = 7.5 Hz); 7.36–7.41
(t, 1H, J = 7.5 Hz); 7.52–7.57 (td, 1H, J = 1.2 Hz and
7.5 Hz); 8.10–8.13 (dd, 1H, J = 1.5 Hz and 8.0 Hz).
2,3-Diphenyl-1-naphthol (1)
To solution of 6.90 g (18.3 mmol) of 2-bromo-2,3-diphe-
nyltetralone in 200 mL of DMF were added 400 mg
(4.60 mmol) of lithium bromide and 1.5 g (20 mmol) of
lithium carbonate. The reaction mixture was heated for 2 h
at 100 °C under nitrogen, poured into 1,000 mL of water
and 20 mL of concentrated HCl and extracted with ethyl
acetate (4 9 100 mL). The organic phase was washed with
water (3 9 100 mL) dried with sodium sulfate and the
solvent was removed on rotary evaporator. The residue was
crystallized from acetic acid and then from heptane. Yield:
3.90 g (72%), m.p. 130–131 °C (lit1 m.p. 127–128 °C). 1H
NMR (300 MHz, DMSO-d6) d 7.04–7.26 (m, 10H); 7.46
(s, 1H); 7.49–7.55 (m, 2H); 7.88–7.93 (m, 1H); 8.25–8.29
(m, 1H); 8.97 (s, 1H). 13C NMR (75 MHz, CDCl3) d 121.2,
122.7, 123.5, 125.7, 126.6, 127.1, 127.7, 127.8, 128.0,
129.4, 130.0, 131.4, 133.9, 135.5, 139.9, 141.5, 148.6.
Synthesis of 1-(Methylthio)methoxy-2,3-diphenyl
naphthol-d5 (2) and 2-(Methylthio)methyl-2,3-diphenyl
1(2H)-naphthalenone-d5 (3)
A solution of 200 mg (0.67 mmol) of 2,3-diphenyl-1-
naphthol (1) in 4.0 mL of DMSO-d6 was heated at 180 °C
in a N2 atmosphere. After 30 h no trace of naphthol (1) was
detected by 1H NMR. The reaction mixture was then poured
into 150 mL of water, extracted with ethyl acetate
(4 9 20 mL), the combined organic phase washed with
water (4 9 20 mL), dried with sodium sulfate and the sol-
vent was removed on a rotary evaporator. The residue was
purified by column chromatography (1.9 9 30 cm silica
2-Bromo-2,3-diphenyltetralone
To solution of 14.2 g (48 mmol) of trans-2,3-diphenyltetr-
alone in 750 mL of glacial acetic acid was added dropwise
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