Helvetica Chimica Acta ± Vol. 82 (1999)
1131
Ethyl 2-[4-(Acetyloxy)phenyl]-6-cyano-3,4-dihydro-2H-pyran-4-carboxylate (10d). Residual starting ma-
terials were distilled off (1008/0.02 Torr) to leave pure c-10d (1.35 g, 86%). IR (neat): 3060m, 2228s, 1755vs,
1
7
1
2
725vs, 1635s, 1500s, 1363vs, 1290vs, 1245vs, 1215vs, 1185vs, 1160vs, 1145vs, 1040vs, 1015vs, 970s, 940s, 905vs, 853s,
1
60s. H-NMR (CDCl
3
): 7.38 (m, 2 H (Ar)); 7.12 (m, 2 H (Ar)); 5.91 (dd, J 2.5, 1.7, H� C(5)); 4.99 (dd, J
� C(2)); 4.19 (q, J 7.1, MeCH O); 3.55 (ddd, J 11.4, 6.3, 2.5, H � C(4)); 2.44 (dddd, J 14.1, 6.3,
� C(3)); 2.32 (s, MeCO); 2.15 (dt, J 14.1, 11.4, H � C(3)); 1.28 (t, J 7.1, MeCH
O). 13C-NMR
): 170.1 (COOEt); 169.0 (MeCO); 150.4 (C (Ar)); 135.8 (C (Ar)); 130.0 (C(6)); 126.8 (2 CH (Ar));
1.4, 2.0, H
.0, 1.7, H
a
2
a
a
b
2
(CDCl
3
1
(
2
21.5 (2 CH (Ar)); 113.8 (CN); 113.8 (C(5)); 77.7 (C(2)); 61.3 (MeCH
2
O); 38.4 (C(4)); 31.3 (C(4)); 20.7
MeCO); 13.7 (MeCH
00(4), 162(2), 120(59), 91(5).
-[4-(Acetylamino)phenyl]-3,4-dihydro-2H-pyran-6-carbonitrile ( N-[4-(6-Cyano-3,4-dihydro-2H-pyran-
-yl)phenyl]acetamide; 8h). M.p. 163.5 ± 164.08. R 0.56 (AcOEt). IR (KBr): 3300s, 3250s, 3190s, 3060s, 2215s,
2
O). CI-MS: 333 (100, [M NH
4
] ), 316 (3, [M H] ), 315 (19, M ), 273(10), 227(4),
2
2
1
8
f
665vs, 1638s, 1600vs, 1545vs, 1530vs, 1510vs, 1410vs, 1365s, 1315vs, 1290s, 1260s, 1230s, 1140vs, 1025vs, 960s,
1
30vs, 775s. H-NMR (CDCl
3
): 7.52 (m, 2 H (Ar)); 7.41 (br., NH); 7.29 (m, 2 H (Ar)); 5.77 (ddd, J 5.0, 3.2,
� C(2)); 2.38 (dddd, J 19.0, 10.3, 6.4, 3.2, H � C(4)); 2.23 (dddd, J
� C(4)); 2.19 (s, MeCONH); 2.11 (ddddd, J 14.0, 6.4, 2.8, 2.4, 1.0, H � C(3)); 1.95
): 169.0 (MeCONH); 138.0 (C (Ar)); 135.2 (C (Ar));
29.6 (C(6)); 126.4 (2 CH (Ar)); 120.0 (2 CH (Ar)); 117.1 (C(5)); 114.8 (CN); 78.2 (C(2)); 28.3 (C(3)); 24.3
1
1
(
.0, H� C(5)); 4.88 (dd, J 10.3, 2.4, H
9.0, 5.8, 5.0, 2.8, H
dtd, J 14.0, 10.3, 5.8, H
a
a
b
b
1
3
a
� C(3)). C-NMR (CDCl
3
1
(
1
MeCONH); 21.3 (C(4)). CI-MS: 260 (1, [M NH
62(9), 161(44), 144(1), 120(14), 119(100), 118(14), 117(4), 106(2), 104(3), 91(21), 78(4).
-[4-(Acetylamino)phenyl]-3,4-dihydro-4-methyl-2H-pyran-6-carbonitrile ( N-[4-(6-Cyano-3,4-dihydro-
-methyl-2H-pyran-2-yl)phenyl]acetamide; 9h). FC (AcOEt/hexane 1 : 4) gave a crystalline product (0.83 g,
5%); cis/trans 94 : 6. M.p. 122.4 ± 123.88. R 0.41 (AcOEt/hexane 1 : 2). IR (KBr): 3230vs, 3170s, 3100s, 3070m,
4
] ), 243 (50, [M H] ), 242 (17, M ), 214(4), 187(11),
2
4
6
2
8
f
220s, 1655vs, 1630vs, 1590s, 1525vs, 1510vs, 1405vs, 1367vs, 1305vs, 1263s, 1150s, 1060vs, 1035s, 985s, 965s, 905s,
1
80s, 820vs, 740s. H-NMR (CDCl
3
): c-9h: 7.52 (m, 2 H (Ar)); 7.32 (br., NH); 7.30 (m, Ar); 5.60 (dd, J 2.3,
� C(2)); 2.68 (m, J 11.3, 7.0, 6.0, 2.3, H � C(4)); 2.19 (s, MeCONH);
� C(3)); 1.60 (dt, J 14.0, 11.3, H � C(3)); 1.12 (d, J 7.0, Me� C(4)); t-9h:
): c-9h: 169.0 (MeCONH); 138.1
1
2
5
.7, H� C(5)); 4.90 (dd, J 11.3, 2.0, H
a
a
.14 (dddd, J 14.0, 6.0, 2.0, 1.7, H
a
b
13
.73 (dd, J 4.8, 1.2, H� C(5)); 1.18 (d, J 7.0, Me� C(4)). C-NMR (CDCl
3
(
(
(
C (Ar)); 135.1 (C (Ar)); 128.8 (C(6)); 126.5 (2 CH (Ar)); 122.8 (C(5)); 120.0 (2 CH (Ar)); 114.8 (CN); 78.9
C(2)); 37.9 (C(3)); 24.2 (MeCONH); 28.4 (C(4)); 19.8 (Me� C(4)); t-9h: 74.8 (C(2)); 35.5 (C(3)); 25.7
C(4)); 21.3 (NHCOMe); 17.9 (Me� C(4)). CI-MS: 274 (3, [M NH
4
] ), 257 (49, [M H] ), 256 (19, M ),
2
35(1), 201(5), 162(16), 161(100), 136(2), 120(19), 119(100), 118(17), 106(8), 91(15), 87(3).
Ethyl 2-[4-(Acetylamino)phenyl]-6-cyano-3,4-dihydro-2H-pyran-4-carboxylate (10h). FC (AcOEt/hexane
:2) gave a product with cis/trans 2 :1. IR (KBr): 3280s, 3240s, 3180s, 3110s, 3060s, 2225s, 1725vs, 1660vs, 1640s,
600vs, 1545vs, 1530vs, 1510vs, 1410s, 1365s, 1315s, 1265s, 1245s, 1180vs, 1145s, 1045s, 1015vs, 833vs, 760s. CI-MS:
1
1
3
2
32 (12, [M NH
4
] ), 315 (49, [M H] ), 314 (21, M ), 288 (6), 287 (7), 286 (6), 260 (7), 259 (28), 241 (4),
14 (13), 198 (5), 186 (3), 162 (17), 161 (67), 144 (3), 120 (20), 119 (100), 118 (10), 106 (8), 91 (19), 89 (5), 80
(
12), 79 (15), 77 (6).
Data of Pure c-10h: Crystalline c-10h was obtained on treatment of the crude product with hexane/Et
2
O.
1
M.p. 122.8 ± 124.08. H-NMR (CDCl
.0, H� C(5)); 4.96 (dd, J 11.3, 1.7, H
3
): 7.54 (m, 2 H (Ar)); 7.52 (br., NH); 7.30 (m, 2 H (Ar)); 5.90 (dd, J 2.4,
� C(2)); 4.19 (q, J 7.1, MeCH O); 3.55 (ddd, J 11.3, 6.4, 2.4,
� C(4)); 2.42 (dddd, J 14.0, 6.4, 2.0, 1.7, H � C(3)); 2.19 (s, MeCONH); 2.15 (dt, J 14.0, 11.3, H � C(3));
): 170.4 (COOEt); 169.1 (MeCONH); 138.5 (C (Ar)); 133.8 (C
Ar)); 130.2 (C(6)); 126.5 (2 CH (Ar)); 119.9 (2 CH (Ar)); 114.0 (CN); 113.8 (C(5)); 78.2 (C(2)); 61.4
2
H
1
(
(
a
2
a
a
b
1
3
.29 (t, J 7.1, MeCH
2 3
O). C-NMR (CDCl
MeCH
2
O); 38.6 (C(4)); 31.3 (C(4)); 24.0 (MeCONH); 13.8 (MeCH
2
O).
1
Data of t-10h (from c/t-10 2 :1): H-NMR (CDCl
3
): 7.58 (br., HN); 7.53 (m, 2H (Ar)); 7.29 (m, 2 H (Ar));
� C(2)); 4.23 (q, J 7.1, MeCH O); 3.26 (ddd, J 6.0,
� C(3)); 2.19 (s, MeCONH); 1.95 (ddd, J 14.1, 11.0,
O). 13C-NMR (CDCl
): 170.9 (COOEt); 169.1 (MeCONH); 138.3 (C
Ar)); 134.1 (C (Ar)); 130.4 (C(6)); 126.3 (2 CH (Ar)); 119.9 (2 CH (Ar)); 114.1 (CN); 113.0 (C(5)); 76.4
O); 36.6 (C(4)); 29.7 (C(4)); 24.0 (MeCONH); 13.8 (MeCH O).
5
5
6
(
.90 (dd, J 5.5, 1.6, H� C(5)); 4.94 (dd, J 11.0, 2.3, H
.5, 1.6, H
� C(4)); 2.46 (dddd, J 14.1, 2.3, 2.0, 1.6, H
.0, H
� C(3)); 1.32 (t, J 7.1, MeCH
b
2
a
b
a
2
3
(
C(2)); 61.5 (MeCH
2
2
2
-(4-Chlorophenyl)-3,4-dihydro-2H-pyran-6-carbonitrile (8e). Oil. IR (neat): 3070m, 2230s, 1643vs, 1598m,
1
1
493vs, 1442m, 1295vs, 1288vs, 1236vs, 1145vs, 1090vs, 1040vs, 955s, 932m, 875m, 820s, 778s. H-NMR (CDCl
3
):
� C(2));
� C(4)); 2.12 (ddtd, J 14.0,
� C(3)). C-NMR (CDCl ): 138.1 (C (Ar)); 133.8 (C
7
2
6
.36 (m, 2 H (Ar)); 7.28 (m, 2 H (Ar)); 5.77 (ddd, J 5.1, 3.2, 1.1, H� C(5)); 4.89 (dd, J 10.3, 2.5, H
a
.38 (dddd, J 19.1, 10.3, 6.5, 3.2, H
a
� C(4)); 2.23 (dddd, J 19.1, 5.9, 5.1, 2.5, H
b
13
.5, 2.5, 1.1, H
a
� C(3)); 1.93 (dtd, J 14.0, 10.3, 5.9, H
b
3