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C8); 36.5 (d, C1); 34.7 (t, C6); 29.2 (t, C5); 26.4 (q, C10/C9); 24.7 (q, C9/C10); 22.2 (q, C7). MS (EI,
70 eV): 246 (M+, 4%); 135 (M+−C7H11O, 100%).
2.5. (1R,4RS)-Menthonyl-calix[n]arenes
2.30 g of 6 (9.3 mmol), 488 mg of paraformaldehyde (16.3 mmol), 28 µl of 10 N NaOH (1.1 mmol)
and 16 ml of xylene were refluxed using a Dean–Stark trap filled with activated molecular sieves, 4 Å,
or a small dropping funnel filled with molecular sieves to remove the reaction water. After 9.5 h, 26.5 h
and 33.5 h, 25 µl of 10 N NaOH (1.0 mmol) and 400 mg of paraformaldehyde (13.3 mmol) were added,
and after 51.5 h the reaction mixture was cooled to room temperature and 1.3 ml of 1 N HCl and 100 ml
of diethyl ether were added. This mixture was washed with 50 ml of 1 N HCl and three times with 50
ml water and dried with MgSO4. After removing the solvent, the crude mixture was separated by flash
chromatography using 30% acetone in n-hexane into the following calix[n]arenes:
2.5.1. (1R,4RS)-Menthonyl-calix[5]arene 7
1
200 mg (8.3%); H NMR (CDCl3, 250 MHz, ppm): 8.76 (br s, 1H, OH); 7.19 (br s, 2H, Haromat);
4.14 and 3.50 (two br s, 2H, AB system from Ar–CH2–Ar); 2.5 (br m, 1H, H4); 2.1–2.3 (br m, 1H, H2);
1.9–2.0 (br m, 1H, H2); 1.6–1.8 (br m, 3H, H1, H5, H6); 1.41 (br s, 3H, CH3 9); 1.36 (br s, 3H, CH3 10);
0.89 (br s, 3H, CH3 7). 13C NMR (CDCl3, 63 MHz, ppm): 211.3 (s, C3); 147.7 (s, C40); 142.5 (s, C10);
126.4 (d, C20, C60, C30, C50); 59.9 (d, C4); 52.5, 50.4 (t, C2); 38.4, 38.5, 38.9 (s, C8); 36.3, 32.3 (d,
C1); 34.8, 25.0 (t, C6); 31.6 (t, Ar–CH2–Ar); 29.1, 31.2 (t, C5); 27.9, 27.6 (q, C10 or C9); 23.6, 23.1 (q,
C9 or C10); 22.3, 19.4 (q, C7). FAB-MS: 1313 ([M+Na]+); 1290 ([M−H]+); 1201 ([M+Na−C7H12O]+);
731 ([M−5(C7H12O)]+). HRMS (electrospray ion-source, neg. charged ions): calculated for C85H110O10:
1290.8099; found: 1290.8121.
2.5.2. (1R,4RS)-Menthonyl-calix[6]arene 8
200 mg (8.3%); 1H NMR (CDCl3, 250 MHz, ppm): 10.4 (br s, 1H, OH); 7.09 (br s, 2H, Haromat); 4.2
and 3.5 (two vbr s, 2H, AB system from Ar–CH2–Ar); 2.56–0.83 (signals from menthyl substructure).
13C NMR (CDCl3, 63 MHz, ppm): 211.2 (s, C3); 147.7 (s, C40); 142.6 (s, C10); 128.4 (d, C20, C60);
127.0 (s, C30, C50); 59.9 (d, C4); 52.5, 50.3 (t, C2); 38.6, 39.1 (s, C8); 36.3, 32.3 (d, C1); 34.9, 24.9
(t, C6); 33.1 (t, Ar–CH2–Ar); 29.1, 31.2 (t, C5); 27.7, 27.2 (q, C9 or C10); 23.3, 23.8 (q, C10 or C9);
22.2, 19.5 (q, C7). ESI-MS: 1683.1 ([M+Cs]+); 907.5 ([M+2Cs]+). FAB-MS: 1571.4 (M+Na+); 876.8
([M−6(C7H12O)]+). HRMS (electrospray ion-source, neg. charged ions): calculated for C102H132O12:
1548.9663; found: 1548.9718.
2.5.3. (1R,4RS)-Menthonyl-calix[8]arene 9
300 mg (12.4%); 1H NMR (CDCl3, 250 MHz, ppm): 6.94 (s, 2H, Haromat); 3.2–4.3 (very broad signal,
2H, AB system from Ar–CH2–Ar); 2.5–0.8 (signals from the menthyl substructure). 13C NMR (CDCl3,
63 MHz, ppm); 211.4 (s, C3); 147.1 (s, C40); 142.7 (s, C10); 127.4 (d, C20, C60); 126.9 (s, C30, C50); 59.8
(d, C4); 52.5, 50.4 (t, C2); 38.6, 39.1 (s, C8); 36.3, 32.3 (d, C1); 34.9, 25.0 (t, C6); 33.0 (t, Ar–CH2–Ar);
29.1, 31.3 (t, C5); 27.7 (q, C9 or C10); 23.4 (q, C10 or C9); 22.3, 19.5 (q, C7). FAB-MS: 2088.4
(M+Na+); 1168.9 ([M−8(C7H12O)]+). HRMS (electrospray ion-source, neg. charged ions): calculated
for C136H176O16: 2065.2958; found 2065.2777.