R. Lazny et al. / Tetrahedron 60 (2004) 121–130
127
compound 6b as a light red, sensitive to light and oxygen
solid (3.846 g, 92%). Rf (10% MeOH/DCM) 0.4; dH
(200 MHz, CDCl3) 6.83–6.60 (m, 4H), 3.89 (t, 6.5 Hz,
2H), 3.65 (t, 5.5 Hz, 2H), 3.41 (br s, 2H), 1.90–1.70 (m, 2H),
1.70–1.40 (m, 7H); dC (50.3 MHz, CDCl3) 152.1, 139.6,
116.4, 115.5, 68.4, 62.4, 32.4, 29.2, 25.7, 25.4; nmax(CHCl3)
(4.676 g, 95%, 0.89 mmol of diethylamine/g, theoretical
loading: 0.89 mmol/g). nmax(KBr) 1227 (C–O) cm21; dC
(50.3 MHz, CDCl3) 156.9, 143.6, 121.3, 114.8, 66.9, 65.3,
46.0, 29.8, 13.0. Anal. found: C, 84.36; H, 7.82; N, 3.73.
C80H88N3O2 requires C, 85.52; H, 7.89; N, 3.74.
3624 (OH), 3440, 3366 (N–H), 1238 (C–O–C) cm21
.
4.1.13. 6-[4-(3,3-Diethyltriaz-1-enylo)phenoxy]hexyloxy-
methylpolystyrene (8b). An analogous procedure to that
described for 8a gave the title polymer 8b as a light yellow
powder (4.958 g, 97%, 0.85 mmol of diethylamine/g,
theoretical loading: 0.86 mmol/g). nmax(KBr) 1236 (C–
O) cm21; dC (50.3 MHz, CDCl3) 156.9, 145.0, 121.3, 114.7,
70.3, 68.1, 46.2, 29.7, 29.3, 26.0, 25.9, 12.9. Anal. found: C,
84.76; H, 8.12; N, 3.44. C83H94N3O2 requires C, 85.52; H,
8.13; N, 3.60.
4.1.10. 3-[4-(3,3-Diethyltriaz-1-enyl)phenoxy]propan-1-
ol (7a). To a cooled (210 8C) solution of 3-(4-aminophen-
oxy)propan-1-ol (6a, 4.9 g, 29 mmol) and conc. hydro-
chloric acid (5.3 mL, 63.8 mmol) in ethanol (50 mL) was
added portionwise over 20 min. a cold solution of sodium
nitrite (2.001 g, 29 mmol) in water (5 mL). After 15 min.
the resulting cold solution of the diazonium salt was added
to a cold, stirred mixture of diethylamine (8.4 g, 12 mL,
116 mmol, 4 equiv.) water (10 mL) and crushed ice (ca.
20 g). After 15 min the resulting mixture was allowed to
warm up to room temperature, strongly basified with
potassium hydroxide and extracted with DCM (3£70 mL).
The combined extracts were dried (MgSO4) and the solvent
was evaporated in vacuo to give a crude product.
Purification through dry-column flash chromatography
(5–50% AcOEt/Hex) gave the triazene product as an
orange oil (4.950 g, 68%). Rf (50% AcOEt/Hex) 0.8; dH
(200 MHz, CDCl3) 7.41–7.33 (m, 2H), 6.91–6.84 (m, 2H),
4.13 (t, 6 Hz, 2H), 3.92–3.80 (m, 2H), 3.73 (q, 7 Hz, 4H),
2.11–1.98 (m, 2H), 1.98–1.91 (m, 1H), 1.26 (t, 7 Hz, 6H);
dC (50.3 MHz, CDCl3) 156.4, 144.9, 121.0, 114.4, 65.3,
59.5, br 44.4, 31.8, 12.7; nmax(CHCl3) 3430 (OH) cm21; m/z
(EI) 251 (Mþ, 32), 179 (57), 152 (12), 151 (100), 94 (13), 93
(70), 65 (40), 41 (11). HRMS (EI): Mþ, found: 251.1640.
C13H21O2N3 requires 251.1634.
4.1.14. meta-(3-Hydroxy)propyloxyacetanilide (10a). To
a solution of 3-chloropropan-1-ol (2.836 g, 30 mmol) in dry
acetone (10 mL), was added sodium iodide (4.946 g,
33 mmol) and the mixture was heated under reflux for
24 h. Then meta-hydroxyacetanilide (9, 4.989 g, 33 mmol)
and anhydrous potassium carbonate (6.22 g, 45 mmol)
followed by acetone (10 mL) were added and the mixture
was stirred and heated under reflux. After 20 h the solids
were filtered off and the filtrate was evaporated in vacuo to
give the crude product as a white solid, which was used in
the next step. Mp 92–94 8C; Rf (10% MeOH/DCM) 0.50;
dH (200 MHz, CD3OD) 7.30–7.22 (m, 1H), 7.21–7.13 (m,
1H), 7.07–6.99 (m, 1H), 6.73–6.62 (m, 1H), 4.05 (t, 6 Hz,
2H), 3.73 (t, 6.5 Hz, 2H), 2.10 (s, 3H), 2.05–1.90 (m, 2H).
dC (50.3 MHz, CDCl3) 170.0, 159.2, 139.3, 128.9, 111.7,
109.5, 106.0, 64.1, 58.0, 31.7, 22.4. nmax(KBr) 3282 (OH),
1668 (CvO) cm21; m/z (EI) 209 (Mþ, 14), 150 (7), 149 (6),
110 (15), 109 (100), 81 (14), 80 (12), 43 (30); HRMS (EI);
Mþ, found: 209.1060. C11H15NO3 requires 209.1052.
4.1.11. 6-[4-(3,3-Diethyltriaz-1-enyl)phenoxy]hexan-1-ol
(7b). An analogous procedure to that described for 7a gave
the title compound 7b as a light orange oil (5.353 g, 63%).
Rf (50% AcOEt/Hex) 0.7; dH (200 MHz, CDCl3) 7.39–7.32
(m, 2H), 6.92–6.81 (m, 2H), 3.96 (t, 6.5 Hz, 2H), 3.79–3.60
(m, 6H), 1.90–1.40 (m, 9H), 1.25 (t, 7 Hz, 6H); dC
(50.3 MHz, CDCl3) 156.7, 144.8, 121.1, 114.5, 67.9, 62.3,
br 44.3, 32.4, 29.1, 25.7, 25.4, 12.7; nmax(CHCl3) 3623,
3451 (OH) cm21; m/z (EI) 293 (Mþ, 25), 221 (21), 123 (34),
95 (14), 94 (70), 83 (18), 55 (100), 41 (13). HRMS (EI):
found: 293.2108 (Mþ). C16H27N3O2 requires 293.2103.
4.1.15. meta-(6-Hydroxy)hexyloxyacetanilide (10b). An
analogous procedure to that described for 10a gave the
crude title compound 10b as a white solid, which was used
in the next step. Mp 88–90 8C; Rf (10% MeOH/DCM) 0.60;
dH (200 MHz, CDCl3) 7.38–7.12 (m, 3H), 7.00–6.85 (m,
1H), 6.74–6.60 (m, 1H), 3.96 (t, 6.5 Hz, 2H), 3.67 (t,
6.5 Hz, 2H), 3.20 (t, 7 Hz, 1H), 2.17 (s, 3H), 1.96–1.24 (m,
8H); dC (50.3 MHz, CDCl3) 168.5, 159.6, 139.1, 129.6,
111.8, 110.7, 106.3, 67.9, 62.8, 32.6, 29.1, 25.8. 25.4,
24.5;nmax(KBr) 3307 (OH), 1667 (CvO) cm21; m/z (EI)
251 (Mþ, 8), 151 (21), 110 (11), 109 (100), 81 (8), 55 (15),
43 (20), 41 (11); HRMS (EI); Mþ, found: 251.1515.
C14H21NO3 requires 251.1521.
4.1.12. 3-[4-(3,3-Diethyltriaz-1-enyl)phenoxy]propyloxy-
methylpolystyrene (8a). To a solution of 3-[4-(3,3-
diethyltriaz-1-enyl)phenoxy]propan-1-ol (7a, 5.522 g,
22 mmol, 5 equiv.) in dry THF (30 mL) was added sodium
hydride (0.88 g, 60% dispersion in oil, 22 mmol) and the
mixture was heated under argon to 60 8C for 20 min. After
the resulting solution was cooled to room temperature
Merrifield gel (4 g, Novabiochem, 1% PS-DVB, 200–400
mesh, 1.1 mmol/g) was added and the suspension was
heated to 60 8C with intermittent stirring for 72 h. Then the
polymer was washed successively with a mixture of water
and methanol (1:2, 3£15 mL), methanol (2£15 mL), DCM
(2£15 mL), a mixture of water and DMF (1:2, 3£15 mL),
DMF (3£15 mL), DCM (3£15 mL) and methanol
(3£15 mL). The residual solvent was removed from the
gel in vacuo and the gel was dried to a constant mass (ca.
2 h) under high vacuum to give bright yellow, powder
4.1.16. para-(3-Hydroxy)propyloxyacetanilide (11a).19
An analogous procedure to that described for 10a gave the
crude title compound 11a as a white solid, which was used
in the next step. Mp 93–95 8C; Rf (10% MeOH/DCM) 0.50;
dH (200 MHz, CD3OD) 7.44–7.34 (m, 2H), 6.92–6.80 (m,
2H), 4.04 (t, 6 Hz, 2H), 3.73 (t, 6.5 Hz, 2H), 2.08 (s, 3H),
2.02–1.89 (m, 2H); dC (50.3 MHz, CDCl3) 170.8, 156.5,
132.2, 122.5, 115.0, 65.3, 59.1, 32.8, 23.2; nmax(CHCl3)
3242 (OH), 1655 (CvO) cm21; m/z (EI) 209 (Mþ, 25), 167
(12), 110 (9), 109 (100), 108 (33), 80 (12), 53 (8), 43 (26).
4.1.17. para-(6-Hydroxy)hexyloxyacetanilide (11b).20 An
analogous procedure to that described for 10a gave the