E
D. Y. Ong, S. Chiba
Feature
Synthesis
13C NMR (100 MHz, CDCl3): = 201.9, 138.8, 131.9, 128.9, 121.4, 54.1,
IR (KBr): 2716 (aldehyde C–H), 1715 cm–1 (C=O).
31.2, 25.5, 22.7.
1H NMR (400 MHz, CDCl3): = 9.48 (s, 1 H), 7.83–7.80 (m, 3 H), 7.72
(s, 1 H), 7.51–7.45 (m, 2 H), 7.35 (dd, J = 8.6, 1.8 Hz, 1 H), 2.65–2.59
(m, 2 H), 2.04–1.97 (m, 2 H), 1.84–1.76 (m, 2 H), 1.74–1.67 (m, 2 H).
1-(4-Chlorophenyl)cyclohexane-1-carbaldehyde (2d)20
13C NMR (100 MHz, CDCl3): = 200.7, 137.7, 133.4, 132.4, 128.5,
127.9, 127.5, 126.33, 126.28, 126.1, 125.8, 63.8, 32.5, 24.3.
HRMS (ESI): m/z [M + H]+ calcd for C16H17O: 225.1279; found:
225.1276.
Reaction time: 3 h; workup protocol: 1; eluent system: 2% EtOAc/
hexane; white solid; yield: 94.3 mg (0.423 mmol, 85%) from 1d (110
mg, 0498 mmol). The spectroscopic data for 2d are identical to those
reported in the literature.
1H NMR (400 MHz, CDCl3): = 9.35 (s, 1 H), 7.34 (d, J = 8.6 Hz, 2 H),
7.25 (d, J = 8.6 Hz, 2 H), 2.29–2.26 (m, 2 H), 1.85–1.78 (m, 2 H), 1.67–
1.63 (m, 3 H), 1.53–1.44 (m, 2 H), 1.35–1.31 (m, 1 H).
4-(Naphthalen-2-yl)tetrahydro-2H-pyran-4-carbaldehyde (2i)
Reaction time: 3 h; workup protocol: 1; eluent system: 10% EtOAc/
hexane; white solid; yield: 94.8 mg (0.394 mmol, 79%) from 1i (119
mg, 0.499 mmol); mp 104.8–106.8 °C.
13C NMR (100 MHz, CDCl3): = 201.9, 138.2, 133.3, 129.0, 128.5, 54.0,
31.3, 25.5, 22.7.
IR (KBr): 2698 (formyl C–H), 1728 (C=O), 1107 cm–1 (C–O).
1-(4-Fluorophenyl)cyclohexane-1-carbaldehyde (2e)20
1H NMR (400 MHz, CDCl3): = 9.47 (s, 1 H), 7.87–7.82 (m, 3 H), 7.75
(s, 1 H), 7.53–7.48 (m, 2 H), 7.38 (dd, J = 8.7, 1.9 Hz, 1 H), 3.95 (ddd, J =
11.8, 4.0, 4.0 Hz, 2 H), 3.65 (ddd, J = 11.8, 11.8, 2.4 Hz, 2 H), 2.52–2.49
(m, 2 H), 2.24–2.16 (m, 2 H).
13C NMR (100 MHz, CDCl3): = 200.8, 135.8, 133.4, 132.6, 128.9,
128.0, 127.5, 126.53 (stacked), 126.2, 124.2, 64.9, 52.3, 31.2.
Reaction time: 3 h; workup protocol: 1; eluent system: 2% EtOAc/
hexane; colorless oil; yield: 85.5 mg (0.415 mmol, 83%) from 1e (101
mg, 0.499 mmol). The spectroscopic data for 2e are identical to those
reported in the literature.
1H NMR (400 MHz, CDCl3): = 9.34 (s, 1 H), 7.28 (dd, J = 8.7, 5.4 Hz, 2
H), 7.05 (dd, J = 8.7, 8.7 Hz, 2 H), 2.31–2.27 (m, 2 H), 1.84–1.77 (m, 2
H), 1.68–1.59 (m, 3 H), 1.52–1.43 (m, 2 H), 1.35–1.26 (m, 1 H).
13C NMR (100 MHz, CDCl3): = 202.1, 161.9 (d, J = 246.7 Hz), 135.4,
128.7 (d, J = 8.0 Hz), 115.7 (d, J = 21.2 Hz), 53.8, 31.4, 25.5, 22.7.
19F NMR (376 MHz, CDCl3): = –115.3 to –115.4 (m).
HRMS (ESI): m/z [M + H]+ calcd for C16H17O2: 241.1229; found:
241.1230.
8-Phenyl-1,4-dioxaspiro[4.5]decane-8-carbaldehyde (2j)21
Reaction time: 3 h; workup protocol: 2; eluent system: 15% EtOAc/
hexane; white solid; yield: 88.3 mg (0.359 mmol, 72%) from 1j (122
mg, 0.501 mmol). The spectroscopic data for 2j are identical to those
reported in the literature.
1H NMR (400 MHz, CDCl3): = 9.41 (s, 1 H), 7.37 (dd, J = 7.4, 7.4 Hz, 2
H), 7.32 (d, J = 7.5 Hz, 2 H), 7.27 (t, J = 7.4 Hz, 1 H), 3.97–3.91 (m, 4 H),
2.38–2.35 (m, 2 H), 2.18–2.11 (m, 2 H), 1.77–1.65 (m, 4 H).
1-(Naphthalen-2-yl)cyclopropane-1-carbaldehyde (2f)
Reaction time: 4 h; workup protocol: 2; eluent system: 4% EtOAc/
hexane; white solid; yield: 82.3 mg (0.419 mmol, 84%) from 1f (96.7
mg, 0.500 mmol); mp 67.3–69.3 °C.
IR (KBr): 2754 (formyl C–H), 1713 cm–1 (C=O).
1H NMR (400 MHz, CDCl3): = 9.35 (s, 1 H), 7.85–7.80 (m, 3 H), 7.76
(s, 1 H), 7.50–7.45 (m, 2 H), 7.43 (dd, J = 8.5, 1.7 Hz, 1 H), 1.66–1.63
(m, 2 H), 1.52–1.49 (m, 2 H).
13C NMR (100 MHz, CDCl3): = 201.4, 138.3, 128.9, 127.4, 127.1,
108.1, 64.31, 64.28, 53.5, 31.5, 28.4.
13C NMR (100 MHz, CDCl3): = 201.0, 135.0, 133.3, 132.8, 128.8,
4-Methoxy-2,2-diphenylbutanal (2k)
128.3, 128.0, 127.71, 127.65, 126.3, 126.1, 37.6, 16.2.
HRMS (ESI): m/z [M + H]+ calcd for C14H13O: 197.0966; found:
197.0969.
Reaction time: 3 h; workup protocol: 1; eluent system: 4% EtOAc/
hexane; colorless oil; yield: 94.8 mg (0.373 mmol, 75%) from 1k (126
mg, 0.500 mmol).
IR (KBr): 2720 (aldehyde C–H), 1728 (C=O), 1115 (C–O), 1082 cm–1
(C–O).
1-(Naphthalen-2-yl)cyclobutane-1-carbaldehyde (2g)
1H NMR (400 MHz, CDCl3): = 9.74 (s, 1 H), 7.36 (dd, J = 7.2, 7.2 Hz, 4
H), 7.30 (t, J = 7.2 Hz, 2 H), 7.21 (d, J = 7.2 Hz, 4 H), 3.22 (s, 3 H), 3.16 (t,
J = 7.0 Hz, 2 H), 2.60 (t, J = 7.0 Hz, 2 H).
Reaction time: 3 h; workup protocol: 2; eluent system: 2% EtOAc/
hexane; colorless oil; yield: 85.9 mg (0.409 mmol, 82%) from 1g (104
mg, 0.500 mmol).
IR (KBr): 2704 (formyl C–H), 1714 cm–1 (C=O).
13C NMR (100 MHz, CDCl3): = 197.9, 140.0, 129.0, 128.6, 127.4, 69.1,
1H NMR (400 MHz, CDCl3): = 9.61 (s, 1 H), 7.85–7.81 (m, 3 H), 7.62
(s, 1 H), 7.51–7.45 (m, 2 H), 7.24 (dd, J = 8.4, 1.9 Hz, 1 H), 2.85–2.79
(m, 2 H), 2.55–2.48 (m, 2 H), 2.12–1.92 (m, 2 H).
13C NMR (100 MHz, CDCl3): = 199.4, 138.2, 133.4, 132.3, 128.7,
127.72, 127.68, 126.4, 126.0, 125.2, 124.4, 57.7, 28.4, 15.9.
61.7, 58.6, 34.4.
HRMS (ESI): m/z [M + H]+ calcd for C17H19O2: 255.1385; found:
255.1380.
(E)-2,2-Dimethyl-5-phenylpent-4-enal (2l)22
HRMS (ESI): m/z [M + H]+ calcd for C15H15O: 211.1123; found:
211.1122.
Reaction time: 3 h; workup protocol: 2; eluent system: 2% EtOAc/
hexane; clear oil; yield: 75.4 mg (0.401 mmol, 80%) from 1l (92.4 mg,
0.499 mmol). The spectroscopic data for 2l are identical to those re-
ported in the literature.
1-(Naphthalen-2-yl)cyclopentane-1-carbaldehyde (2h)
1H NMR (400 MHz, CDCl3): = 9.54 (s, 1 H), 7.33 (d, J = 7.3 Hz, 2 H),
7.29 (dd, J = 7.3, 7.3 Hz, 2 H), 7.21 (t, J = 7.3 Hz, 1 H), 6.42 (dt, J = 15.6,
1.2 Hz, 1 H), 6.11 (dt, J = 15.6, 7.6 Hz, 1 H), 2.37 (dd, J = 7.6, 1.2 Hz, 2
H), 1.11 (s, 6 H).
Reaction time: 3 h; workup protocol: 2; eluent system: 2% EtOAc/
hexane; white solid; yield: 91.5 mg (0.408 mmol, 82%) from 1h (111
mg, 0.500 mmol); mp 75.3–76.8 °C.
© 2020. Thieme. All rights reserved. Synthesis 2020, 52, A–J