Helvetica Chimica Acta Vol. 87 (2004)
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1.975 (s, (Me(19,20)); 1.982 (s, (Me(20')); 2.050 (s, AcOÀC(3)); 2.058( s, (AcOÀC(3')); 2.122 (dd, J 15.9, 9.7,
HaxÀC(4)); 2.417 (d, J 9.7, HÀC(6')); 2.456 (dd, J 17.1, 5.7, HeqÀC(4)); 5.501 (m, HÀC(4')); 5.07 (m,
HeqÀC(3)); 5.34 (m, HeqÀC(3')); 5.441 (d, J 15.5, 9.7, HÀC(7')); ca. 6.15 (m, HÀC(7,8,8',10,10')); ca. 6.63 (m,
HÀC(11,11',12,12',14,14',15,15')). 13C-NMR (150 MHz, CDCl3): 12.71 (Me(19)); 12.77 (Me(20,20')); 13.07
(Me(19')); 21.44 (Me(18)); 22.94 (Me(18')); 25.26 (Me(17')); 28.49 (Me(17)); 28.94 (Me(16')); 29.97 (Me(16));
33.42 (C(1')); 38.44 (C(1)); 39.56 (C(4)); 44.03 (C(2)); 54.89 (C(6')); 68.39 (C(3)); 68.83 (C(3')); 119.95 (C(4'));
124.74 (C(11')); 124.87 C(11)); 125.26 (C(7)); 125.59 (C(5)); 128.28 (C(7')); 130.07 (C(15,15')); 130.94 (C(10'));
131.40 (C(10)); 132.58(C(14,14 ')); 134.97 (C(9')); 135.55 (C(9)); 136.44 (C(12')); 137.62 (C(12)); 137.83 (C(6));
138.63 (C(8)); 140.41 (C(5')); 170.74, 170.83 (AcO).
4. Lutein-3,3'-diyl Bis(2-chloroacetate) (1d). In the same equipment as in Exper. 2, a soln. of 657 mg of 1a in
10 ml of THF and 5 ml of pyridine was treated at r.t. dropwise with AcCl until 1a disappeared (TLC). The
solvents were then evaporated in vacuo, followed by extraction of the carotenoids with Et2O, and thorough
washing with H2O and brine, and drying (Na2SO4). Chromatography on a column of silica gel (Merck 60, as
before), degassed and filled as a slurry, and development with ligroin/AcOEt 9 :1 yielded a crystalline, red
residue. Recrystallization from THF/heptane gave 1d (625 mg, 75%). Shining red crystals. M.p. (in vacuo) 1788.
UV/VIS (CH2Cl2): 272.0 (4.28), 430.8 (4.86), 455.0 (5.03), 484.4 (4.99). CD (CH2Cl2): 245.6 (6.17), 285.2
(À2.68), 341.2 (1.31). IR (KBr): 2961, 2922, 2858, 1757, 1192, 1167, 964. 1H-NMR (500 MHz, CDCl3): 0.885 (s,
Me(17')); 1.015 (s, Me(16')); 1.086* (s, Me(16)); 1.113* (s, Me(17)); 1.502 (dd, J 14.1, 4.7, HaxÀC(2')); ca. 1.64
(HeqÀC(2')); 1.667 (s, Me(18')); 1.729 (s, Me(18)); 1.83 (dd, J ?, HaxÀC(2)); 1.88 (dd, J ?, HeqÀC(2')); 1.902
(s, Me(19')); 1.966 (s, Me(19,19',20,20')); 2.405 (d, J 9.3, HÀC(6')); ca. 2.47 (dd-like, J ?, HeqÀC(4)); 4.036,
4.050 (2s, CH2Cl); ca. 5.1 (m, HÀC(3)); 5.41 (m, HÀC(3',7')); ca. 6.06 6.3 (m, HÀC(7,8,8',10,10')); ca. 6.26
(dd-like, J ?, HÀC(14,14')); ca. 6.36 (dd, J 15.0, 5.0, HÀC(12,12')); ca. 6.62 (m, HÀC(11,11',15,15')). Anal.
calc. for C44H58Cl2O4 (721.85): C 73.21, H 8.10, Cl 9.82; found: C 73.03/73.06, H 8.18/8.25, Cl 9.38/9.69.
5. 3,3'-Dimethoxylutein (1e; simplified and improved procedure according to [31]). In the same equipment
as in Exper. 2, 203 mg of 1a were dissolved in 10 ml of benzene. After addition of 160 mg of t-BuOK, the soln.
was warmed to 358. The potassium salt of 1a soon precipitated. After addition of 4 ml MeI, the precipitate
slowly disappeared. The mixture was stirred at the same temp. for 12 h. Then, evaporation of the solvents in
vacuo, followed by extraction of the colored compounds and purification by chromatography on silica gel (as
described before) with benzene/AcOEt 4 :1 yielded from the brownish-red main fraction 153 mg (73%; [31]:
6%) of 1e. Red crystals from Et2O/hexane. M.p. (in vacuo): 1648 ([31]: 1558). UV/VIS: 271.3 (4.36), 432.0
(4.94), 455.0 (5.11), 484.1 (5.07). CD (CH2Cl2): 229.0 (De 2.14), 247.5 (5.13), 289.0 (À1.96). IR (CHCl3): 2964,
2926, 1089, 970). 1H-NMR (600 MHz, CDCl3): 0.844 (s, Me(17')); 0.973 (s, Me(16')); 1.074 (s, Me(16,17)); 1.394
(d, J 11.9, HaxÀC(2')); 1.411 (dd, J 12.4, 3.3, HaxÀC(2)); 1.567 (?); 1.622 (s, Me (18')); 1.739 (s, Me(18));
1.766 (dd, J 5.9, 5.8, HeqÀC(2')); 1.831 (d-like, J 12.2, HeqÀC(2)); 1.911 (s, Me(19')); 1.966 (s, Me(20,20');
1.973 (s, Me(19)); 2.01 (dd, J 16.9, 9.6, HaxÀC(4)); ca. 2.42 (m, HÀC(6'), HeqÀC(4)); 3.365 (s, MeOÀC(3'));
3.381 (s, MeOÀC(3)); ca. 3.51 (m, HÀC(3)); ca. 3.78( m, HÀC(3')); 5.441 (dd, J 10.0, 9.9, HÀC(7')); 5.601
(−s×, HÀC(4')); ca. 6.15 (m, HÀC(7,8',10,10')); 6.252 (d-like, HÀC(14,14')); 6.502 (dd, J 6.3, HÀC(12,12')).
13C-NMR (150 MHz, CDCl3): 12.75 (Me(19)); 12.81 (Me(20,20')); 13.11 (Me(19')); 21.70 (Me(18)); 22.95
(Me(18')); 24.29 (Me(17')); 28.69 (Me(16)); 29.45 (Me(16')); 30.26 (Me(17)); 33.89 (C(1')); 36.71 (C(1)); 39.28
(C(4)); 40.42 (C(2')); 44.54 (C(2)); 55.15 (C(6')); 55.58(MeO ÀC(3')); 55.78(MeO ÀC(3)); 73.67 (C(3)); 74.60
(C(3')); 121.89 (C(4')); 124.84 (C(11')*); 124.95 (C(11)*); 125.72 (C(7)); 126.12 (C(5)); 128.98 (C(7')); 130.03
(C(15)); 130.07 (C(15')); 130.72 (C(10)); 131.25 (C(10')); 132.54 (C14,14')); 135.73 (C(9,9')); 136.41 (C(13'));
136.48(C(13)); 137.58(C(12,12 ')); 137.64 (C(8')); 137.85 (C(5')); 138.21 (C(6)); 138.3 (C(8)). CI-MS: 597 (96,
.
.
M
), 565 (20, [M À MeO] ).
6. Lutein-3,3'-diyl Bis(2,2-dimethylpropanoate) (1f). In the same equipment as in Exper. 2, a soln. of 188 mg
of 1a in 6 ml of THF and 4 ml of pyridine was treated at 508 intermittently with small droplets of pivaloyl
chloride until 1a disappeared (TLC). Usual workup with Et2O, H2O and brine yielded a redish residue, which
was chromatographed on a column of silica gel (as described before). From the deep red main fraction 200 mg of
crystalline 1f were isolated. Recrystallisation from benzene/MeOH yielded red glittering thin leaflets. M.p. (in
vacuo) 202 2038. UV/VIS (CH2Cl2): 270.5 (4.38), 455.1 (5.13), 484.3 (5.08). CD (CH 2Cl2): 245.8 (8.58), 285.0
(À4.31), 343.6 (1.76), 455.2 (with fine structure; 3.61). IR (CHCl3, strong bands): 2967, 1784, 1741, 1721, 1275,
1171, 1107, 1063, 969. 1H-NMR (600 MHz, CDCl3): 0.887 (s, Me(17')); 1.035 (s, Me(16')); 1.090 (s, Me(16)); 1.125
(Me(17)); 1.201, 1.209 (2s, t-Bu); 1.265 (?); 1.403 (dd, J 16.1, 4.2, HaxÀC(2')); 1.579 (t, J 11.9, HaxÀC(2));
1.668( s, Me(18')); 1.735 (s, Me(18)); 1.781 (d with fine structure, HeqÀC(2)); 1.839 (dd, J 14.1, 5.9,
HeqÀC(2')); 1.915 (s, Me(19')); 1.977 (s, Me(20,20')); 1.982 (s, Me(19)); 2.108( dd, J 15.7, 9.3, HaxÀC(4)); 2.378
(d, J 9.5, HÀC(6')); 2.434 (dd, J 17.0, 5.6, HeqÀC(4)); 5.043 (m, HÀC(3)); 5.293 (m, HÀC(3')); 5.484 (s,