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128.4, 128.3, 125.9, 124.1, 123.2, 122.0, 117.4, 111.9, 34.0 ppm.
ESI-MS: m/z = 285.1 [M + H]+. HRMS (ESI): calcd. for C20H17N2
[M + H]+ 285.1392; found 285.1392.
[1D]-1,3-Diphenylprop-2-yn-1-ol (9): Yield 64%; Rf = 0.45 (PE/EA
= 9:1); light yellow oil. 1H NMR (400 MHz, CDCl3): δ = 7.59–
7.62 (m, 2 H), 7.46–7.49 (m, 2 H), 7.28–7.42 (m, 6 H), 2.47 (s, 1
H) ppm. 13C NMR (100 MHz, CDCl3): δ = 140.6, 131.8, 128.7,
128.6, 128.5, 128.3, 126.8, 122.4, 88.7, 86.6, 64.8 (t, 1JCD = 22.6 Hz)
ppm. ESI-MS: m/z = 192.1 [M – OH]+. HRMS (ESI): calcd. for
C15H10D [M – OH]+ 192.0924; found 192.0930.
Deuterium-Labeling Experiment: To a 25 mL flask were sequen-
tially added anhydrous ZnCl2 (dried before the reaction, 136 mg,
0.75 mmol), CuCl (5 mg, 0.05 mmol), a toluene (dry, 2 mL) solu-
tion of
9 (0.105 g, 0.5 mmol), and 2-aminopyridine (0.07 g,
0.75 mmol) under Ar. The reaction mixture was stirred at 120 °C
for 24 h before it was cooled to room temperature and quenched
with NH3·H2O (1.5 mL), diluted with water (5 mL), and extracted
with CH2Cl2 (2ϫ 10 mL). The combined organic layers were
washed with brine (10 mL), dried with MgSO4, and the solvent was
removed under reduced pressure. The residue was purified by silica
gel chromatography (petroleum ether/EtOAc/Et3N = 16:2:1) to af-
ford a mixture of 10 and 4a (37:13, determined by 1HNMR;
0.103 g, 72%) as light yellow solid, m.p. 155–158 °C, Rf = 0.44 (PE/
[5]
[6]
1
EA = 4:1). H NMR (400 MHz, CDCl3): δ = 7.77–7.80 (m, 2 H),
7.67–7.69 (m, 2 H), 7.41–7.45 (m, 2 H), 7.23–7.37 (m, 4 H), 7.13–
7.19 (m, 3 H), 6.67–6.71 (m, 1 H), 4.49 (s, 0.52 H of 4a), 4.47 (s,
0.74 H of 10) ppm. 13C NMR (100 MHz, CDCl3): δ = 144.9, 144.2,
136.8, 136.7, 134.5, 129.0, 128.6, 128.2, 127.7, 126.9, 124.1, 123.4,
1
117.6, 117.6, 112.2, 29.8, 29.6 (t, JCD = 19.6 Hz) ppm. ESI-MS:
m/z = 285.1 (4a, 31) [M + H]+, 286.0 (10, 100) [M + D]+. HRMS
(ESI): calcd. for C20H16DN2 [M + H]+ 286.1455; found 286.1449.
Supporting Information (see footnote on the first page of this arti-
1
cle): Copies of the H and 13C NMR spectra.
Acknowledgments
We thank the National Natural Foundation of China (NSFC)
(20872019) and Fudan University for financial support. We are
grateful to Dr. Bangguo Wei and Dr. Hanqing Dong for helpful
discussions.
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