The Journal of Organic Chemistry
Article
(4700); IR (ATR, cm−1) 3291, 2967, 2933, 2877, 2160, 2030, 1624,
1539, 1469, 1407, 1359, 1316, 1204, 1165, 1069, 991, 915, 805, 726,
679; EI-MS m/z 347.2 (100), 328.1 (20). Anal. Calcd for
C18H24BF2N3O: C, 62.27; H, 6.97; N, 12.10. Found: C, 62.12; H,
6.88; N, 12.07.
1400, 1360, 1324, 1239, 1186, 1123, 1019, 979, 938, 846, 767, 715,
693; EI-MS m/z 652.3 (100). Anal. Calcd for C42H49BN4O2: C, 77.29;
H, 7.57; N, 8.58. Found: C, 77.02; H, 7.38; N, 8.34.
Compound 4a. Prepared according to the general procedure from
BOD-8 (40 mg, 0.04 mmol), ethanol (1 mL), [Pd(PPh3)2Cl2] (6 mg,
0.009 mmol), toluene (6 mL) and triethylamine (2 mL); stirred
overnight; column chromatography on silica gel eluting with CH2Cl2/
petroleum ether (80:20) gave 4a (25 mg, 70%): 1H NMR (300 MHz,
Compound 2d. Prepared according to the general procedure from
BOD-6 (30 mg, 0.07 mmol), glycine ethyl ester hydrochloride (32 mg,
0.21 mmol), [Pd(PPh3)2Cl2] (11 mg, 0.015 mmol), benzene (6 mL),
and triethylamine (2 mL); stirred overnight; column chromatography
3
3
CDCl3) δ = 1.37 (t, 6H, J = 7.2 Hz), 3.80 (s, 6H), 4.34 (q, 4H, J =
7.2 Hz), 7.24 (t, 2H, 3J = 7.2 Hz), 7.39 (AB sys, 8H, JAB = 8.7 Hz, νoδ
= 246.3 Hz), 7.46 (t, 2H, 3J = 7.2 Hz), 7.54 (AB sys, 8H, JAB = 9.0 Hz,
νoδ = 314.9 Hz), 7.61 (d, 2H, 3J = 8.1 Hz), 7.93 (s, 1H), 7.94 (d, 2H,
3J = 8.1 Hz); 13C NMR {1H} (75.4 MHz, CDCl3) δ = 14.5, 55.5, 61.1,
98.4, 113.6, 115.2, 118.5, 123.3, 124.9, 126.1, 128.4, 128.9, 129.0,
129.6, 131.4, 132.6, 133.9, 151.3, 160.5, 166.4; 11B NMR (128.4 MHz,
CDCl3) δ = −7.24 (s); UV−vis (CH2Cl2) λ nm (ε, M−1·cm−1) 644
(102300), 357 (25900), 288 (77300); IR (ATR, cm−1) 3049, 2977,
2933, 2836, 1710, 1618, 1594, 1552, 1516, 1460, 1383, 1307, 1269,
1242, 1174, 1146, 1095, 1028, 960, 857, 789, 769, 747, 696; EI-MS m/
z 812.1 (100), 767.2 (10). Anal. Calcd for C53H41BN2O6: C, 78.33; H,
5.08; N, 3.45. Found: C, 78.55; H, 5.22; N, 3.44.
1
on silica gel eluting with CH2Cl2 gave 2d (10 mg, 30%): H NMR
(200 MHz, CDCl3) δ = 1.31 (t, 3H, 3J = 7 Hz), 2.43 (s, 3H), 2.53 (s,
6H), 2.61 (s, 3H), 2.65 (s, 3H), 4.21 (d, 2H, 3J = 5.1 Hz), 4.25 (q, 2H,
3J = 7.0 Hz), 6.14 (s, 1H); 13C NMR {1H} (75.4 MHz, CDCl3) δ =
13.4, 14.3, 14.8, 15.3, 17.1, 17.8, 41.7, 61.8, 123.1, 131.1, 137.8, 143.1,
143.9, 150.1, 157.5, 165.6, 170.1; 11B NMR (128.4 MHz, CDCl3) δ =
3.60 (t, JB−F = 32.0 Hz); UV−vis (CH2Cl2) λ nm (ε, M−1·cm−1) 497
(85000), 473 (sh, 28500), 369 (5200); IR (ATR, cm−1) 3249, 2982,
2890, 1739, 1630, 1548, 1513, 1472, 1406, 1316, 1294, 1210, 1161,
1066, 1026, 1010, 979, 854, 792, 749, 725, 683; EI-MS m/z 391.1
(100), 372.2 (20). Anal. Calcd for C19H24BF2N3O3.H2O: C, 55.76; H,
6.40; N, 10.27. Found: C, 55.49; H, 6.32; N, 10.04.
Compound 3a. Prepared according to the general procedure from
BOD-7 (60 mg, 0.08 mmol), ethanol (1 mL), [Pd(PPh3)2Cl2] (10 mg,
0.016 mmol), benzene (6 mL), and triethylamine (2 mL); stirred
overnight; column chromatography on silica gel eluting with CH2Cl2/
petroleum ether (50:50) gave 3a (35 mg, 70%): 1H NMR (300 MHz,
CDCl3) δ = 1.10 (t, 6H, 3J = 7.5 Hz), 1.37 (t, 6H, 3J = 7.2 Hz), 2.38 (s,
6H), 2.48 (q, 4H, 3J = 7.5 Hz), 2.66 (s, 3H), 2.82 (s, 6H), 4.35 (q, 4H,
3J = 7.2 Hz), 7.66 (AB sys, 8H, JAB = 8.3 Hz, νoδ = 146.6 Hz); 13C
NMR {1H} (75.4 MHz, CDCl3) δ = 14.1, 14.5, 14.8, 15.2, 17.4, 17.6,
61.0, 121.8, 129.3, 130.3, 131.5, 132.8, 134.9, 140.0, 152.0, 166.5; 11B
NMR (128.4 MHz, CDCl3) δ = −9.8 (s); UV−vis (CH2Cl2) λ nm (ε,
M−1·cm−1) 516 (87200), 491 (sh, 25700), 372 (7000), 290 (56800),
277 (56400); IR (ATR, cm−1) 3043, 2967, 2928, 2869, 1713, 1603,
1550, 1475, 1402, 1361, 1321, 1306, 1268, 1172, 1108, 1019, 960, 935,
855, 768, 715, 694; EI-MS m/z 626.2 (80). Anal. Calcd for
C40H43BN2O4: C, 76.67; H, 6.92; N, 4.47. Found: C, 76.55; H,
6.89; N, 4.38.
Compound 4b. Prepared according to the general procedure from
BOD-8 (40 mg, 0.04 mmol), glycine ethyl ester hydrochloride (18 mg,
0.12 mmol), [Pd(PPh3)2Cl2] (6 mg, 0.009 mmol), toluene (6 mL),
and triethylamine (2 mL); stirred overnight; column chromatography
on silica gel eluting with CH2Cl2/MeOH (99:1) gave 4b (10 mg,
25%): 1H NMR (300 MHz, CDCl3) δ = 1.30 (t, 6H, 3J = 7.1 Hz), 3.80
3
3
(s, 6H), 4.20 (d, 4H, J = 4.9 Hz), 4.25 (q, 4H, J = 7.1 Hz), 6.56 (t,
2H, 3J = 5.1 Hz), 7.24 (t, 2H, 3J = 7.1 Hz), 7.29 (AB sys, 8H, JAB = 8.5
Hz, νoδ = 176.2 Hz), 7.46 (t, 2H, 3J = 7.1 Hz), 7.54 (AB sys, 8H, JAB
=
8.9 Hz, νoδ = 314.5 Hz), 7.61 (d, 2H, 3J = 8.5 Hz), 7.93 (s, 1H), 7.94
3
(d, 2H, J = 7.7 Hz); 13C NMR {1H} (75.4 MHz, CDCl3) δ = 14.3,
42.0, 55.5, 61.8, 98.1, 113.6, 115.2, 118.5, 123.4, 124.8, 126.1, 126.6,
128.4, 128.6, 131.4, 131.7, 132.0, 132.6, 133.9, 151.3, 160.5, 167.0,
170.2; 11B NMR (128.4 MHz, CDCl3) δ = −7.39 (s). UV−vis
(CH2Cl2) λ nm (ε, M−1·cm−1) 644 (85800), 361 (20700), 283
(62200), 262 (85900); IR (ATR, cm−1) 3285, 2975, 2931, 2837, 1741,
1640, 1614, 1592, 1552, 1458, 1383, 1309, 1236, 1211, 1174, 1145,
1094, 1027, 965, 853, 752, 710; EI-MS m/z 927.1 (100), 824.2 (20).
Anal. Calcd for C57H47BN4O8·H2O: C, 72.46; H, 5.23; N, 5.93. Found:
C, 72.24; H, 5.04; N, 5.64.
Compound 3b. Prepared according to the general procedure from
BOD-7 (50 mg, 0.07 mmol), 2-propanol (1 mL), [Pd(PPh3)2Cl2] (10
mg, 0.016 mmol), benzene (6 mL), and triethylamine (2 mL); stirred
overnight; column chromatography on silica gel eluting with CH2Cl2/
petroleum ether (gradient from 50:50 to 70:30) gave 3b (25 mg,
45%): 1H NMR (300 MHz, CDCl3) δ = 1.10 (t, 6H, 3J = 7.7 Hz), 1.35
(d, 12H, 3J = 6.2 Hz), 2.38 (s, 6H), 2.48 (q, 4H, 3J = 7.6 Hz), 2.66 (s,
Compound 5. A solution of 1b (100 mg, 0.17 mmol) in DMF/
EtOH (10/10 mL) was degassed with argon for 20 min and cooled to
0 °C. Then a cold solution (<15 °C) of ICl (28 mg, 0.17 mmol) in
ethanol (5−10 mL) was added dropwise. The reaction mixture was
stirred at 0 °C for 30 min and then at rt for 2 h. Saturated aqueous
NaHCO3 solution was added. The organic phase was washed with
water 3 times, dried over MgSO4, and evaporated. The residue was
purified by column chromatography on silica gel eluting with AcOEt/
petroleum ether (40:60) to give 5 as an orange powder (34 mg, 61%):
1H NMR (300 MHz, CDCl3) δ = 1.34 (s, 3H), 1.36 (s, 3H), 1.44 (t,
3H), 2.82 (s, 6H), 5.22 (sep, 2H, 3J = 6.2 Hz), 7.64 (AB sys, 8H, JAB
=
8.6 Hz, νoδ = 145.2 Hz); 13C NMR {1H} (75.4 MHz, CDCl3) δ =
14.1, 14.8, 15.2, 17.4, 17.6, 22.0, 68.5, 129.2, 129.2, 130.2, 130.3, 131.5,
132.8, 134.9, 140.0, 152.0, 166.0; 11B NMR (128.4 MHz, CDCl3) δ =
−9.8 (s); UV−vis (CH2Cl2) λ nm (ε, M−1·cm−1) 516 (78900), 490
(sh, 23000), 372 (6700), 289 (52900), 277 (52400); IR (ATR, cm−1)
2964, 2931, 2870, 1712, 1603, 1549, 1479, 1402, 1360, 1322, 1266,
1172, 1092, 960, 934, 854, 765, 715, 693; EI-MS m/z 654.2 (100),
611.2 (35). Anal. Calcd for C42H47BN2O4: C, 77.06; H, 7.24; N, 4.28.
Found: C, 76.84; H, 7.02; N, 3.98.
3
3H, J = 7.1 Hz), 2.74 (s, 3H), 2.82 (s, 3H), 3.37 (s, 6H), 3.55 (m,
3
4H), 3.65 (m, 4H), 4.19 (s, 4H), 4.43 (q, 2H, J = 7.1 Hz), 6.08 (s,
1H), 7.80 (AB sys, 4H, JAB = 8.1 Hz, νoδ = 234.3 Hz); 13C NMR {1H}
(75.4 MHz, CDCl3) δ = 14.5, 15.1, 16.5, 17.2, 17.6, 59.1, 59.7, 61.6,
68.8, 71.9, 84.9, 123.0, 128.6, 129.7, 130.5, 131.3, 140.2, 141.3, 142.8,
154.7, 157.9, 166.1; 11B NMR (128.4 MHz, CDCl3) δ = −9.96 (s);
UV−vis (CH2Cl2) λ nm (ε, M−1·cm−1) 514 (89300), 488 (sh, 25300),
378 (6300), 316 (6100); IR (ATR, cm−1) 3061, 2981, 2909, 2879,
2840, 2818, 2160, 1717, 1608, 1539, 1512, 1401, 1347, 1304, 1272,
1153, 1077, 1025, 983, 854, 733, 693; EI-MS m/z 710.1 (100), 666.0
(35). Anal. Calcd for C34H40BIN2O6: C, 57.48; H, 5.68; N, 3.94.
Found: C, 57.18; H, 5.40; N, 3.72.
Compound 3c. Prepared according to the general procedure; from
BOD-7 (59 mg, 0.117 mmol), propylamine (1.5 mL), [Pd(PPh3)2Cl2]
(10 mg, 0.014 mmol), and benzene (5 mL); stirred overnight (the
solvent partially evaporated because there was no water in the cooling
apparatus); column chromatography on silica gel eluting with CH2Cl2/
1
AcOEt (gradient from 100:0 to 80:20) gave 3c (30 mg, 57%): H
NMR (300 MHz, CDCl3) δ = 0.97 (t, 6H, 3J = 7.4 Hz), 1.09 (t, 6H, 3J
= 7.5 Hz), 1.62 (sext, 4H, 3J = 7.4 Hz), 2.38 (s, 6H), 2.47 (q, 4H, 3J =
7.5 Hz), 2.66 (s, 3H), 2.81 (s, 6H), 3.40 (dt, 4H, 3J = 7.4 Hz, 3J = 5.6
Hz), 6.057 (t, 2H, 3J = 5.6 Hz), 7.51 (AB sys, 8H, JAB = 8.4 Hz, νoδ =
63.3 Hz); 13C NMR {1H} (75.4 MHz, CDCl3) δ = 11.6, 14.2, 14.9,
15.2, 17.4, 17.6, 23.1, 41.9, 99.8, 126.6, 128.4, 128.8, 129.2, 130.3,
131.8, 132.8, 133.0, 134.9, 152.0, 167.2; UV−vis (CH2Cl2) λ nm (ε,
M−1·cm−1) 516 (76900), 489 (sh, 21600), 373 (6200); IR (ATR,
cm−1) 3603, 3253, 3078, 2959, 2931, 2871, 1629, 1605, 1549, 1479,
Compound 6. Prepared according to the general procedure from 5
(65 mg, 0.06 mmol), glycine ethyl ester hydrochloride (80 mg, 0.60
mmol), [Pd(PPh3)2Cl2] (12 mg, 0.02 mmol), benzene (9 mL), and
triethylamine (3 mL); stirred overnight; column chromatography on
silica gel eluting with AcOEt/petroleum ether (gradient from 50:50 to
1
80:20) gave 6 (16 mg, 40%): H NMR (300 MHz, CDCl3) δ = 1.28
3
3
(t, 3H, J = 7.1 Hz), 1.36 (s, 3H), 1.44 (t, 3H, J = 7.1 Hz), 1.48 (s,
5046
dx.doi.org/10.1021/jo300477p | J. Org. Chem. 2012, 77, 5036−5048