4.6.1. (1RS,2SR)-2-(Trifluoromethyl)-3,6-dihydro-2H-thiopyran 1-oxide (5a) and
(1RS,2RS)-2-(trifluoromethyl)-3,6-dihydro-2H-thiopyran 1-oxide (5b).
Pale brown oil, yield 50 %, Rf = 0.15 (hexane–EtOAc, 2:1). Mixture of the diastereomeric
sulfoxides 5a and 5b in ratio 4.5:1. 1H NMR (400MHz, CDCl3): 2.46÷2.57 (m, 5.5H, H-3eq + H-
3ax*), 2.79–2.94 (m, 5.5H, H-3ax + H-3eq*), 3.17 (ddq, 1H, 3JHH = 12.5 Hz, 4.1 Hz, 3JHF = 8.5 Hz,
H-2), 3.35 (dm, 1H, 2JHH = 18.1 Hz, H-6ax), 3.51÷3.56 (m, 5.5H, H-6eq+H-6ax*), 3.64 (ddq, 4.5H,
3
2
3
3JHH = 10.1 Hz, 5.3 Hz, JHF = 8.4 Hz, H-2*), 3.83 (dd, 4.5H, JHH = 16.0 Hz, JHH = 5.9 Hz, H-
13
6eq*), 5.63-6.73 (m, 5.5H, H-5 + H-5*), 5.85–5.95 (m, 4.5H, H-4*), 6.02–6.09 (m, 1H, H-4). C
NMR (100 MHz, CDCl3): 16.3 (q, 3JCF = 2.0 Hz, C-3), 23.6 (q, 3JCF = 3.0 Hz, C-3*), 47.2 (s, C-6),
49.4 (s, C-6*), 55.7 (q, 2JCF = 27 Hz, C-2), 60.8 (q, 2JCF = 26 Hz, C-2*), 115.6 (s, C-5), 118.0 (s, C-
1
1
5*), 124.7 (q, JCF = 281 Hz, CF3*), 124.9 (q, JCF = 280 Hz, CF3), 126.5 (s, C-4), 126.9 (s, C-
4*).19F NMR (188 MHz, CDCl3): –67.36 (d, 13.5F, 3JHF = 8.4 Hz, CF3*), –69.37 (d, 3F, 3JHF = 8.5
Hz, CF3). GC/MS, m/z (rel. int.): 184 (13) [M]+, 164 (11) [M-HF]+, 135 (18), 115 (100) [M-CF3]+,
95 (30), 69 (16) [CF3]+, 39 (49). Anal. calcd. for C6H7F3OS: C, 39.13; H, 3.83; S, 17.41; found: C,
39.20; H, 3.88; S, 17.35.
4.6.2. (1RS,2SR)-4,5-dimethyl-2-(trifluoromethyl)-3,6-dihydro-2H-thiopyran-1-oxide 6a and
(1RS,2RS)-4,5-dimethyl-2-(trifluoromethyl)-3,6-dihydro-2H-thiopyran-1-oxide 6b
Light brown oil, yield 53%, Rf = 0.18 (CCl4 – EtOAc, 5:2). Mixture of the diastereomers 6a
and 6b in ratio 4:1. Data for isomer 6a. 1H NMR (400MHz, CDCl3): 1.75 (s, 3H, CH3), 1.78 (s, 3H,
CH3), 2.41 (dd, 1H, 2JHH = 17.8 Hz, 3JHH = 9.7 Hz, H-3ax), 2.72 (dd, 1H, 2JHH = 17.8 Hz, 3JHH = 5.6
3
3
2
Hz, H-3eq), 3.48 (ddq, 1H, JHH = 9.7 Hz, 5.6 Hz, JHF = 8.5 Hz, H-2), 3.55 (AB, 1H, JHH = 15.0
2
13
Hz, H-6A), 3.59 (AB, 1H, JHH = 15.0 Hz, H-6B). C NMR (CDCl3): 19.1 (s, CH3), 19.7 (s, CH3),
29.2 (q, 3JCF = 2 Hz, C-3), 54.6 (s, C-6), 63.1 (q, 2JCF = 26 Hz,C-2), 118.7 (s, C-5), 124.9 (q, 1JCF
=
281 Hz, CF3), 127.6, (s, C-4). 19F NMR (282 MHz, CDCl3): –67.69 (d, 3F, 3JFH = 8.5 Hz). GC/MS,
m/z (rel. int.): 212 (100) [M]+, 196 (6) [M-O]+, 163 (96) [M-H-SO]+, 143 (37) [M-CF3]+, 123 (57),
79 (52), 69 (28)[CF3]+, 39 (87). Data for isomer 6b. H NMR (400 MHz, CDCl3): 1.76 (s, 3H,
1
CH3), 1.81, (s, 3H, CH3), 2.33 (dd, 1H, 2JHH = 16.5 Hz, 3JHH = 3.5 Hz, H-3eq), 2.91 (dd, 1H, 2JHH
=
3
3
3
16.5 Hz, JHH = 11.8 Hz, H-3eq), 3.12 (ddq, 1H, JHH = 11.8 Hz, 3.5 Hz, JHF = 7.9 Hz, H-2),
3.31÷3.34 (m, 2H, 2H-6). 13C NMR (100 MHz, CDCl3): 19.5 (s, CH3), 19.8 (s, CH3), 22.0 (q, 3JCF
=
2
1
2.2 Hz, C-3), 52.3 (s, C-6), 56.1 (q, JHH = 27.5 Hz, C-2), 115.1 (s, C-5), 125.2 (q, JCF = 281 Hz,
CF3), 125.9 (s, C-4). 19F NMR (282 MHz, CDCl3): –69.15 (d, 2F, 3JFH = 7.9 Hz). GC/MS, m/z (rel.
int.): 212 (100) [M]+, 196 (6) [M-O]+, 163 (87) [M-H-SO]+, 143 (28) [M-CF3]+, 123 (43), 79 (44),
69 (20)[CF3]+, 39 (57). Anal. calcd. for C8H11F3OS: C, 45.28; H, 5.22; S, 15.11; found: C, 45.12; H,
5.02; S, 14.93.
4.6.3. (1RS,2RS,6RS)-6-acetoxy-2-(trifluoromethyl)-3,6- dihydro-2H-thiopyran-1-oxide 7a,
(1RS,2SR,6RS)-6-acetoxy-2-(trifluoromethyl)-3,6-
dihydro-2H-thiopyran-1-oxide
7b
and
(1RS,2SR,6RS)- 6-acetoxy-2-(trifluoromethyl)-3,6- dihydro-2H-thiopyran-1-oxide 7c.
Yellow oil, 52%, Rf = 0.18 (CCl4 – ethyl acetate 5:2). Mixture of isomers 7a, 7b, 7c in ratio
6.6:1.3:1. NMR data for isomer 7a. 1H NMR (400 MHz, CDCl3): 2.25 (s, 3H, CH3), 2.53 (AB, 2JHH
= 19.4 Hz, 3JHH =11.9 Hz, 2.7 Hz, 4JHH = 2.5 Hz, H-3ax), 2.86 (AB, 2JHH = 19.4 Hz, 3JHH = 5.0 Hz,
4
3
3
3
5.1 Hz, JHH = 1.5 Hz, H-3eq), 3.94 (ddq, 1H, JHH = 11.9 Hz, JHH = 5.0 Hz, JHF = 8.3 Hz, H-2),
5.88 (dddd,1H, 3JHH = 6.2 Hz, 10.4 Hz, 4JHH = 2.5 Hz, 1.5 Hz, H-5), 6.13 (ddd, 1H, 3JHH = 10.4 Hz,
5.1 Hz, 2.7 Hz, H-4), 6.45 (d, 1H, 3JHH = 6.2 Hz, H-6). 13C NMR (100 MHz, CDCl3): 20.3 (s, CH3),
3
2
24.5 (q, JCF = 3 Hz, 3-CH2), 55.1 (q, JCF = 26.7 Hz, 2-CH), 75.2 (s, 6-CH), 119.9 (s,C-5), 124.8
(q, JCF = 280.6 Hz, CF3) 132.5 (s, C-4), 169.1 (s, C=O). 19F NMR(282 MHz, CDCl3): –66.61 (d,
1
3F, 3JHH = 8.3 Hz, CF3). Selected NMR data for isomer 7b. 1H NMR (400 MHz, CDCl3): 3.99 (ddq,
1H, 3JHH = 9.8 Hz, 5.1 Hz, 3JHF = 8.4 Hz, H-2), 5.57 (dddd, 1H, 3JHH = 10.7 Hz, 2.5 Hz, 4JHH = 2.5
3
4
Hz, 2.5 Hz, H-5), 5.94 (ddd, JHH = 10.7 Hz, 5.1 Hz, JHH = 2.5 Hz, H-4) 6.49÷6.52 (m, 1H, H-6).
13C NMR (100 MHz, CDCl3): 20.1 (s, CH3), 24.5 (q, 3JCF = 2 Hz, C-3), 60.2 (q, 2JCF = 27 Hz, C-2),
87.5 (s, C-6), 122.3 (s,C-5), 128.2 (s, C-4), 169.5 (s, C=O). 19F NMR(282 MHz, CDCl3): –66.85 (d,