The Journal of Organic Chemistry
Article
78.5, 55.4, 20.3; HRMS calcd for C17H16BrNO 329.0415, found
329.0410.
J = 7.2 Hz, 2 H); 13C NMR (100 MHz CDCl3) δ 150.2, 139.0, 138.0,
134.3, 128.8, 128.7, 128.5, 128.48, 128.3, 128.0, 125.1, 125.0, 122.5,
116.2, 79.6, 53.3; HRMS calcd for C22H19NO 313.1467, found
313.1464.
4-Methyl-2-phenyl-6-(4-(trifluoromethyl)phenyl)-3,6-dihydro-2H-
1
1,2-oxazine (3e): yellow oil (45.2 mg, 60%); H NMR (600 MHz,
CDCl3) δ 7.60−7.54 (m, 4 H), 7.28−7.26 (m, 2 H), 7.09 (d, J = 8.4
Hz, 2 H), 6.97 (t, J = 8.4 Hz, 1 H), 5.73 (s, 1 H), 5.55 (s, 1 H), 3.77
(AB quartets, J = 7.2 Hz, 2 H), 1.89 (s, 3 H); 13C NMR (150 MHz,
CDCl3) δ 150.1, 143.7.0, 132.3, 130.2 (q, JC−F = 32.3 Hz), 128.8,
128.1, 125.3, 125.3, 122.4, 122.0, 115.9, 78.5, 55.6, 20.3; HRMS calcd
for C18H16F3NO 319.1184, found 319.1180.
3-Methyl-2,4,6-triphenyl-3,6-dihydro-2H-1,2-oxazine (3n): white
solid (47.5 mg, 66%); melting point 144.5−146 °C; H NMR (400
1
MHz CDCl3) δ 7.50−7.47 (m, 4 H) 7.42 (t, J = 7.2 Hz, 2 H), 7.35−
7.23 (m, 6 H), 7.09−7.06 (m, 2 H), 6.89 (t, J = 1.6 Hz, 1 H), 6.36 (d, J
= 2.8 Hz, 1 H) 5.58 (d, J = 3.6 Hz, 1 H) 4.76−4.74 (m, 1 H),1.16 (d, J
= 6.4 Hz, 3 H) ; 13C NMR (100 MHz CDCl3) δ 148.7, 141.2, 140.3,
138.1, 128.7, 128.7, 128.2, 128.0, 127.9, 127.8, 126.2, 123.5, 121.0,
115.7, 78.9, 55.9, 12.5; HRMS calcd for C23H21NO 327.1623, found
327.1616.
4-Methyl-2-phenyl-6-(p-tolyl)-3,6-dihydro-2H-1,2-oxazine (3f):
1
yellow oil (70.4 mg, 84%); H NMR (400 MHz CDCl3) δ 7.34 (d,
J = 7.6 Hz, 2 H), 7.26 (t, J = 8 Hz, 2 H), 7.18 (d, J = 8 Hz, 2 H), 7.11
(d, J = 8 Hz, 2 H), 6.95 (t, J = 7.6 Hz, 1 H), 5.74 (s, 1 H), 5.50 (s, 1
H), 3.77 (AB quartets, J = 7.2 Hz, 2 H), 2.34 (s, 3 H), 1.89 (s, 3 H);
13C NMR (100 MHz CDCl3) δ 150.3, 138.0, 136.5, 131.4, 129.1,
128.7, 128.1, 123.1, 122.0, 115.8, 79.11, 55.3, 21.2, 20.3; HRMS calcd
for C18H19NO 265.1467, found 265.1459.
3-Methyl-2,4,6-triphenyl-3,6-dihydro-2H-1,2-oxazine (3n′): pale
1
yellow oil (18.6 mg, 25%); H NMR (400 MHz CDCl3) δ 7.50−
7.36 (m, 9 H), 7.33−7.28 (m, 3 H), 7.17 (d, J = 7.6 Hz, 2 H), 6.95 (t, J
= 7.6 Hz, 1 H), 6.12 (s, 1 H), 5.66 (s, 1 H), 4.79−4.75 (m, 1 H), 1.28
(d, J = 6.4 Hz, 3 H); 13C NMR (100 MHz CDCl3) δ 148.5, 140.4,
138.5, 137.9, 128.9, 128.7, 128.7, 128.6, 128.2, 128.0, 125.9, 125.2,
121.5, 115.9, 79.5, 55.8, 14.5; HRMS calcd for C23H21NO 327.1623,
found 327.1626.
6-(4-Methoxyphenyl)-4-methyl-2-phenyl-3,6-dihydro-2H-1,2-ox-
azine (3g): yellow oil (58.1 mg, 72%); 1H NMR (400 MHz CDCl3) δ
7.36 (d, J = 8.4 Hz, 2 H), 7.26−7.22 (m, 2 H), 7.09 (d, J = 8.4 Hz, 2
H), 6.93 (t, J = 6.0 Hz, 1 H), 6.89 (d, J = 8.8 Hz, 2 H), 5.72 (s, 1 H),
5.46 (s, 1 H), 3.79 (s, 3 H), 3.76−3.74 (AB quartets, J = 7.2 Hz, 2 H),
1.88 (s, 3 H); 13C NMR (100 MHz CDCl3) δ 159.6, 150.2, 131.7,
131.5, 129.6, 128.7, 123.1, 122.0, 115.8, 113.7, 78.9, 55.3, 55.2, 20.3;
HRMS calcd for C18H19NO2 281.1416, found 281.1412.
4-Methyl-6-(naphthalen-2-yl)-2-phenyl-3,6-dihydro-2H-1,2-oxa-
zine (3h): pale yellow oil (50.4 mg, 65%); 1H NMR (400 MHz
CDCl3) δ 7.87 (s, 1 H), 7.85−7.81 (m, 3 H), 7.59 (d, J = 8.8 Hz, 1
H),7.47 (m, 2 H), 7.26 (t, J = 7.2 Hz, 2 H), 7.13 (d, J = 8.0 Hz, 2 H),
6.95 (t, J = 8.0 Hz, 1 H), 5.84 (s, 1 H), 5.69 (s, 1 H),3.82 (AB quartets,
J = 7.2 Hz, 2 H), 1.91 (s, 3 H); 13C NMR (100 MHz, CDCl3) δ 150.2,
137.0, 133.3, 133.2, 131.8, 128.7, 128.1, 128.1, 127.6, 127.2, 126.1,
126.0, 125.9, 122.8, 122.1, 115.9, 79.4, 55.4, 20.4; HRMS calcd for
C21H19NO 301.1467, found 301.1469.
6-Methyl-2,4-diphenyl-3,6-dihydro-2H-1,2-oxazine (3o): yellow
1
oil (73.2 mg, 84%); H NMR (400 MHz CDCl3) δ 7.44 (d, J = 8.0
Hz, 2 H), 7.39−7.3 (m, 5 H), 7.23 (d, J = 8.0 Hz, 2 H), 7.03 (t, J = 7.6
Hz, 1 H), 6.19 (d, J = 2 Hz, 1 H), 4.86−4.84 (m, 1 H), 4.26−4.06 (AB
quartets, J = 7.2 Hz, 2 H), 1.43 (d, J = 5.6 Hz, 3 H); 13C NMR (100
MHz CDCl3) δ 150.4, 139.2, 133.4, 128.8, 128.6, 127.8, 127.1, 125.0,
122.3, 116.0, 73.6, 53.2, 19.1; HRMS calcd for C17H17NO 251.1310,
found 251.1312.
6-Ethyl-2,4-diphenyl-3,6-dihydro-2H-1,2-oxazine (3p): yellow oil
(57.8 mg, 69%); 1H NMR (600 MHz CDCl3) δ 7.43 (d, J = 8.4 Hz, 2
H), 7.36−7.27 (m, 5 H), 7.21 (d, J = 8.4 Hz, 2 H), 7.01 (t, J = 7.2 Hz,
1 H), 6.21 (s, 1 H),4.63−4.59 (m, 1 H), 4.25−4.06 (AB quartets, J =
7.2 Hz, 2 H), 1.82−1.69 (m, 2 H), 1.13 (t, J = 7.2 Hz, 3H); 13C NMR
(100 MHz CDCl3) δ 150.5, 138.3, 133.8, 128.9, 128.6, 127.8, 126.0,
125.0, 122.1, 115.8, 78.7, 53.4, 26.7, 10.1; HRMS calcd for C18H19NO
265.1467, found 265.1457.
2-Phenyl-6-propyl-5-(thiophene-2-yl)-3,6-dihydro-2H-1,2-oxazine
(5a): yellow oil (52.8 mg, 66%); 1H NMR (600 MHz CDCl3) δ 7.28−
7.21 (m, 2 H), 7.20 (d, J = 1.2 Hz, 1 H), 7.07−6.93 (m, 4 H), 6.93 (s,
1 H), 5.98 (m, 1 H), 4.53−4.49 (m, 1 H), 4.39−4.24 (m, 1 H), 4.23−
4.21 (m, 1 H), 2.02−1.70 (m, 2 H), 1.50−1.38 (m, 2 H) 0.86 (t, J =
7.4 Hz, 3 H); 13C NMR (150 MHz, CDCl3) δ 148.0, 142.9, 132.6,
129.0, 127.5, 124.1, 122.1, 121.6, 119.7, 116.5, 63.6, 58.2, 34.3, 20.4,
14.1; HRMS calcd for C17H19NOS 285.1187, found 285.1183.
2-Phenyl-6-propyl-5-(thiophene-3-yl)-3,6-dihydro-2H-1,2-oxazine
(5b): yellow oil (50.4 mg, 63%); 1H NMR (600 MHz CDCl3) δ 7.32−
7.31 (d, J = 3.0 Hz, H), 7.29−7.26 (m, 2 H), 7.21−7.19 (m, 2 H), 7.08
(dd, J = 8.4, 1.2 Hz, 2 H), 6.93 (t, J = 1.2 Hz, 1 H) 5.98−5.97 (m, 1
H), 4.55−4.39 (m, 1 H), 4.27 (m, 1 H), 4.26−4.23 (m, 1 H), 1.99−
1.67 (m, 2 H), 1.55−1.37 (m, 2 H), 0.85 (t, J = 7.2 Hz, 3 H); 13C
NMR (150 MHz CDCl3) δ 148.2, 140.2, 133.4, 129.0, 126.0, 125.0,
121.4, 119.7, 119.1, 116.4, 63.9, 58.0, 34.2, 20.4, 14.1; HRMS calcd for
C17H19NOS 285.1187, found 285.1185.
6-(Benzo[d][1,3]dioxol-5-yl)-4-methyl-2-phenyl-3,6-dihydro-2H-
1
1,2-oxazine (3i): yellow oil (57.3 mg, 73%); H NMR (400 MHz,
CDCl3) δ 7.28−7.25 (m, 2 H), 7.10 (d, J = 8.4 Hz, 2 H), 6.97−6.90
(m, 3 H), 6.94 (d, J = 8.0 Hz, 1 H), 5.94 (s, 2 H), 5.70 (s, 1 H), 5.43
(s, 1 H), 3.75 (AB quartets, J = 7.2 Hz, 2 H), 1.89 (s, 3 H); 13C NMR
(100 MHz CDCl3) δ 150.2, 147.6, 147.5, 133.4, 131.8, 128.7, 122.9,
122.1, 122.0, 115.8, 108.7, 108.0, 101.03, 79.1, 55.2, 20.3; HRMS calcd
for C18H17NO3 295.1208, found 295.1208.
6-(Furan-3-yl)-4-methyl-2-phenyl-3,6-dihydro-2H-1,2-oxazine
(3j): yellow and brown oil (60.3 mg, 67%); 1H NMR (400 MHz
CDCl3) δ 7.45 (s, 1 H), 7.38 (s, 1 H), 7.29−7.25 (m, 2 H), 7.10−7.08
(m, 2 H), 6.97 (t, J = 7.2 Hz, 1 H), 6.48 (s, 1 H), 5.72 (s, 1 H), 5.47 (s,
1 H), 3.72 (AB quartets, J = 7.2 Hz, 2 H),1.86 (s, 3 H); 13C NMR
(100 MHz CDCl3) δ 150.2, 143.1, 140.8, 131.8, 128.8, 124.5, 122.1,
122.1, 115.8, 109.9, 71.9, 55.2, 20.2; HRMS calcd for C15H15NO2
241.1103, found 241.1106.
6-(Furan-2-yl)-4-methyl-2-phenyl-3,6-dihydro-2H-1,2-oxazine
1
(3k): yellow and brown oil (62.1 mg, 69%); H NMR (400 MHz,
CDCl3) δ 7.42 (s, 1 H), 7.27 (t, J = 7.2 Hz, 2 H), 7.09 (d, J = 8.0 Hz, 2
H), 6.96 (t, J = 7.2 Hz, 1 H), 6.35−6.34 (d, J = 6.0 Hz, 2 H), 5.77 (s, 1
H), 5.53 (s, 1 H), 3.73 (AB quartets, J = 7.2 Hz, 2 H), 1.89 (s, 3 H);
13C NMR (100 MHz CDCl3) δ 152.8, 150.0, 142.8, 133.2, 128.7,
4-Methyl-6-phenyl-2-(p-tolyl)-3,6-dihydro-2H-1,2-oxazine (6a):
1
yellow oil (65.4 mg, 71%); H NMR (400 MHz CDCl3) δ 7.44 (d,
J = 8.4 Hz, 2 H), 7.37−7.30 (m, 3 H), 7.08−7.01 (m, 4 H), 5.74 (s, 1
H), 5.52 (s, 1 H), 3.73 (AB quartets, J = 7.2 Hz, 2 H), 2.27 (s, 3 H),
1.88 (s, 3 H); 13C NMR (100 MHz CDCl3) δ 148.0, 139.7, 131.7,
131.6, 129.3, 128.3, 128.1, 128.0, 122.9, 116.2, 79.2, 55.8, 20.6, 20.3;
HRMS calcd for C18H19NO 265.1467, found 265.1457.
2-[4-(tert-Butyl)phenyl)]-4-methyl-6-phenyl-3,6-dihydro-2H-1,2-
oxazine (6b). yellow oil (77.8 mg, 73%); 1H NMR (400 MHz CDCl3)
δ 7.44 (d, J = 7.2 Hz, 2 H), 7.36−7.27 (m, 5 H), 7.05 (d, J = 8.8 Hz, 2
H), 5.73 (s, 1 H), 5.51 (s, 1 H), 3.74 (AB quartets, J = 7.2 Hz, 2 H),
1.88 (s, 3 H), 1.27 (s, 9 H); 13C NMR (100 MHz CDCl3) δ 147.8,
145.1, 139.7, 131.6, 128.3, 128.1, 128.0, 125.5, 122.9, 115.9, 79.2, 55.6,
34.1, 31.9, 20.3; HRMS calcd for C21H25NO 307.1936, found
307.1929.
122.2, 119.6, 115.9, 110.3, 109.4, 72.4, 54.9, 20.3; HRMS calcd for
C15H15NO2 241.1103, found 241.1105.
4-Methyl-2-phenyl-6-(thiophene-2-yl)-3,6-dihydro-2H-1,2-oxa-
zine (3l): yellow and brown oil (57.3 mg, 67%); 1H NMR (400 MHz,
CDCl3) δ 7.28−7.23 (m, 3 H), 7.09−7.07 (m, 3 H), 6.98−6.93 (m, 2
H), 5.81 (s, 1 H), 5.70(s, 1 H), 3.79−3.70 (m, 2 H), 1.88 (s, 3 H); 13C
NMR (100 MHz CDCl3) δ 149.9, 143.0, 132.1, 128.7, 126.3, 126.3,
126.2, 122.3, 122.2, 115.9, 74 0.5, 55.0, 20.2; HRMS calcd for
C15H15NOS 257.0874, found 257.0876.
2,4,6-Triphenyl-3,6-dihydro-2H-1,2-oxazine (3m): pale yellow oil
1
(68.4 mg, 90%); H NMR (400 MHz CDCl3) δ 7.5 (m, 4 H), 7.40−
7.27 (m, 8 H), 7.19 (d, J = 8.6 Hz, 2 H), 6.99 (t, J = 7.2 Hz, 1 H), 6.39
(d, J = 1.6 Hz, 1 H), 5.73 (d, J = 2.4 Hz, 1 H), 4.36−4.22 (AB quartets,
4310
dx.doi.org/10.1021/jo500009x | J. Org. Chem. 2014, 79, 4306−4311