Z. Huang, J. Xu / Tetrahedron 69 (2013) 1050e1056
1053
reaction was monitored by TLC until complete disappearance of the
xanthate. After evaporation of the solvent, the residue was chroma-
tographed on a silica gel column to yield the addition product 3.
6.0 Hz, 1H in CH2), 2.81 (ddd, J¼13.6, 10.4, 5.6 Hz, 1H in CH2), 3.75
(dddd, J¼8.4, 7.1, 6.9, 5.3 Hz, 1H, CH), 3.80 (ddd, J¼13.8, 6.9, 6.9 Hz,
1H in CH2), 3.85 (ddd, J¼13.8, 7.3, 7.3 Hz, 1H in CH2), 4.59 (dq,
J¼10.3, 7.1 Hz, 1H in CH2), 4.61 (dq, J¼10.3, 7.1 Hz, 1H in CH2),
7.15e7.20 (m, 3H, ArH), 7.26 (dd, J¼7.3, 5.8 Hz, 2H, ArH), 7.72 (dd,
J¼5.5, 3.1 Hz, 2H, ArH), 7.85 (dd, J¼5.5, 3.1 Hz, 2H, ArH). 13C NMR
4.3.1. O-Ethyl S-1-phthalimidoheptan-3-yl dithiocarbonate (3a). The
reaction was complete after addition of 35 mol % of DLP. Yellow oil;
yield: 488 mg, 62%. 1H NMR (CDCl3, 400 MHz) (
d
, ppm) 0.91 (t,
(CDCl3, 100 MHz) (
d, ppm) 13.7, 33.1, 33.3, 33.5, 35.6, 48.2, 69.9,
J¼7.2 Hz, 3H, CH3), 1.38 (t, J¼7.1 Hz, 3H, CH3), 1.21e1.56 (m, 4H,
2CH2), 1.68 (dddd, J¼14.4, 8.5, 5.6, 4.9 Hz, 1H in CH2), 1.82 (dddd,
J¼14.4, 10.1, 5.6, 5.2 Hz, 1H in CH2), 2.05 (dddd, J¼14.1, 7.2, 6.9,
6.9 Hz, 1H in CH2), 2.08 (dddd, J¼14.1, 7.5, 7.2, 7.2 Hz, 1H in CH2),
3.72 (dddd, J¼7.6, 7.2, 6.9, 5.6 Hz, 1H, CH), 3.81 (ddd, J¼13.7, 7.2,
7.2 Hz, 1H in CH2), 3.85 (ddd, J¼13.7, 7.5, 7.5 Hz, 1H in CH2), 4.65 (q,
J¼7.1 Hz, 2H, CH2), 7.72 (dd, J¼5.5, 3.1 Hz, 2H, ArH), 7.85 (dd, J¼5.5,
123.2, 126.0, 128.3, 128.4, 132.1, 133.9, 141.1, 168.2, 213.7. IR (nmax
,
cmꢁ1) 3059, 3025, 1772, 1712, 1218, 1050. HRMS (ESI) calcd for
C
22H24NO3S2 [MþH]þ m/z 414.1198; found 414.1197.
4.3.6. O-Ethyl S-4-phenyl-1-phthalimidobutan-3-yl dithiocarbonate
(3f). The reaction was complete after addition of 32.5 mol % of DLP.
Yellow oil; yield: 583 mg, 73%.1H NMR (CDCl3, 400 MHz) (
d, ppm) 1.36
3.1 Hz, 2H, ArH). 13C NMR (CDCl3, 100 MHz) (
d
, ppm) 13.7, 13.9, 22.5,
(t, J¼7.1 Hz, 3H, CH3), 2.02 (dddd, J¼14.1, 7.2,7.2, 6.9Hz,1HinCH2), 2.07
(dddd, J¼14.1, 7.2, 7.2, 6.6 Hz,1H in CH2), 3.02 (dd, J¼13.8, 6.9 Hz, 1H in
CH2), 3.08 (dd, J¼13.8, 6.9 Hz,1H in CH2), 3.77 (ddd, J¼13.8, 7.2, 6.6 Hz,
1H in CH2), 3.86 (ddd, J¼13.8, 7.2, 6.9 Hz,1H in CH2), 3.95 (dddd, J¼7.2,
7.2, 6.9, 6.9 Hz, 1H, CH), 4.55 (dq, J¼10.7, 7.1 Hz, 1H in CH2), 4.58 (dq,
J¼10.7, 7.1 Hz, 1H in CH2), 7.17e7.22 (m, 1H, ArH), 7.24e7.27 (m, 4H,
ArH), 7.71 (dd, J¼5.5, 3.1 Hz, 2H, ArH), 7.83 (dd, J¼5.5, 3.1 Hz, 2H, ArH).
28.9, 33.2, 33.4, 35.7, 48.7, 69.7, 123.2, 132.1, 133.9, 168.2, 214.2. IR
(
C
nmax, ) 1772, 1713, 1216, 1049. HRMS (ESI) calcd for
cmꢁ1
18H23NNaO3S2 [MþNa]þ m/z 388.1017; found 388.1018.
4.3.2. O-Ethyl S-1-phthalimidononan-3-yl dithiocarbonate (3b). The
reaction was complete after addition of 15 mol % of DLP. Yellow oil;
13C NMR (CDCl3, 100 MHz) (
d
, ppm) 13.7, 32.0, 35.7, 40.1, 49.6, 69.8,
yield: 534 mg, 73%. 1H NMR (CDCl3, 400 MHz) (
d, ppm) 0.88 (t,
123.2,126.7,128.3,129.3,132.0,133.9,137.9,168.1, 213.5. IR(nmax, cmꢁ1
)
J¼7.0 Hz, 3H, CH3), 1.38 (t, J¼7.1 Hz, 3H, CH3), 1.20e1.50 (m, 8H,
4CH2), 1.67 (dddd, J¼15.1, 9.7, 5.6, 4.8 Hz, 1H in CH2), 1.80 (dddd,
J¼15.1, 10.5, 5.6, 5.4 Hz, 1H in CH2), 2.06 (dddd, J¼14.3, 7.5, 6.8,
6.8 Hz, 1H in CH2), 2.08 (dddd, J¼14.3, 7.5, 7.3, 7.3 Hz, 1H in CH2),
3.72 (dddd, J¼8.0, 6.8, 5.6, 5.6 Hz, 1H, CH), 3.80 (ddd, J¼13.8, 7.3,
6.8 Hz, 1H in CH2), 3.85 (ddd, J¼13.8, 7.5, 7.3 Hz, 1H in CH2), 4.60 (q,
J¼7.1 Hz, 2H, CH2), 7.72 (dd, J¼5.5, 3.1 Hz, 2H, ArH), 7.85 (dd, J¼5.5,
3054, 3027, 1771, 1712, 1218, 1049. HRMS (ESI) calcd for C21H22NO3S2
[MþH]þ m/z 400.1041; found 400.1043.
4.3.7. O-Ethyl
bonate (3h). The reaction was complete after addition of 25 mol % of
DLP. Yellow oil; yield: 427 mg, 63%.1H NMR (CDCl3, 400 MHz) (
, ppm)
S-1-hydroxy-4-phthalimidobutan-2-yl
dithiocar-
d
1.39 (t, J¼7.1 Hz, 3H, CH3), 2.07 (dddd, J¼14.0, 7.1, 7.1, 6.3 Hz,1H in CH2),
2.10 (s, 1H, OH), 2.24 (dddd, J¼14.0, 7.1, 7.1, 6.3 Hz, 1H in CH2),
3.82e3.94 (m, 5H, 2CH2 & CH), 4.61 (q, J¼7.1 Hz, 2H, CH2), 7.72 (dd,
J¼5.1, 3.6Hz,2H,ArH), 7.85(dd,J¼5.1, 3.6Hz, 2H, ArH).13CNMR(CDCl3,
3.1 Hz, 2H, ArH). 13C NMR (CDCl3, 100 MHz) (
d, ppm) 13.7, 14.0, 22.5,
26.7, 29.0, 31.6, 33.2, 33.5, 35.7, 48.7, 69.7, 123.2, 132.1, 133.9, 168.2,
214.2. IR (nmax, cmꢁ1) 1772, 1713, 1215, 1050. HRMS (ESI) calcd for
C
20H28NO3S2 [MþH]þ m/z 394.1511; found 394.1500.
100 MHz) (d, ppm) 13.7, 29.7, 35.7, 50.6, 64.2, 70.2, 123.3, 132.0, 134.0,
168.2, 213.4. IR (nmax, cmꢁ1) 3463, 1771, 1710, 1219, 1050. HRMS (ESI)
calcd for C15H17NNaO4S2 [MþNa]þ m/z 362.0497; found 362.0493.
4.3.3. S-1-Cyclohexyl-4-phthalimidobutan-2-yl O-ethyl dithiocar-
bonate (3c). The reaction was complete after addition of 15 mol % of
DLP. Yellow oil; yield: 641 mg, 79%. 1H NMR (CDCl3, 400 MHz) (
d,
4.3.8. O-Ethyl S-1-phenoxy-4-phthalimidobutan-2-yl dithiocarbonate
ppm) 1.13e1.76 (m, 13H in cyclohexylmethylene), 1.39 (t, J¼7.1 Hz,
3H, CH3), 2.06 (dddd, J¼14.8,13.8, 7.7, 6.4 Hz,1H in CH2), 2.08 (dddd,
J¼14.8,13.2, 7.6, 7.0 Hz,1H in CH2), 3.72e3.87 (m, 3H, CH2 & CH), 4.60
(q, J¼7.1 Hz, 2H, CH2), 7.72 (dd, J¼5.5, 3.1 Hz, 2H, ArH), 7.85 (dd, J¼5.5,
(3i). The reaction was complete after addition of 20 mol % of DLP.
Yellowoil;yield:789 mg, 95%.1H NMR (CDCl3, 400 MHz)(
d, ppm)1.38
(t, J¼7.1 Hz, 3H, CH3), 2.16 (dddd, J¼14.4, 7.4, 6.9, 6.9 Hz, 1H in CH2),
2.42 (dddd, J¼14.4, 6.9, 6.9, 6.4 Hz, 1H in CH2), 3.89 (t, J¼6.9 Hz, 2H,
CH2), 4.12 (dd, J¼11.5, 5.5 Hz,1H in CH2), 4.19 (dd, J¼11.5, 5.5 Hz,1H in
CH2), 4.35e4.40 (m,1H, CH), 4.60 (q, J¼7.1 Hz, 2H, CH2), 6.89e6.95(m,
3H, ArH), 7.23e7.27 (m, 2H, ArH), 7.73 (dd, J¼5.5, 3.1 Hz, 2H, ArH), 7.85
3.1 Hz, 2H, ArH). 13C NMR (CDCl3, 100 MHz) (
d, ppm) 13.7, 26.0, 26.2,
26.4, 32.7, 33.6, 34.2, 34.9, 35.6, 41.0, 46.2, 69.7, 123.1, 132.1, 133.9,
168.2, 214.2. IR (nmax, cmꢁ1) 1772,1714,1214,1049. HRMS (ESI) calcd
for C21H28NO3S2 [MþH]þ m/z 406.1511; found 406.1503.
(dd, J¼5.5, 3.1 Hz, 2H, ArH). 13C NMR (CDCl3, 100 MHz) (
d, ppm) 13.7,
29.7, 35.7, 47.5, 68.8, 70.2,114.6,121.2,123.2,129.4,132.0,133.9,158.3,
168.2, 213.4. IR (nmax, cmꢁ1) 3059, 1772, 1712, 1227, 1050. HRMS (ESI)
calcd for C21H22NO4S2 [MþH]þ m/z 416.0990; found 416.0995.
4.3.4. O-Ethyl S-6-phenyl-1-phthalimidohexan-3-yl dithiocarbonate
(3d). The reaction was complete after addition of 30 mol % of DLP.
Yellow oil; yield: 633 mg, 74%. 1H NMR (CDCl3, 400 MHz) (
d, ppm)
1.36 (t, J¼7.1 Hz, 3H, CH3), 1.52e1.65 (m, 4H, 2CH2), 2.04 (dddd,
J¼14.3, 6.8, 6.8, 6.8 Hz, 1H in CH2), 2.07 (dddd, J¼14.3, 7.3, 7.3,
7.3 Hz, 1H in CH2), 2.61 (ddd, J¼13.7, 7.2, 7.2 Hz, 1H in CH2), 2.68
(ddd, J¼13.7, 7.6, 7.6 Hz, 1H in CH2), 3.70e3.86 (m, 3H, CH2 & CH),
4.57 (dq, J¼11.6, 7.1 Hz, 1H in CH2), 4.60 (dq, J¼11.6, 7.1 Hz, 1H in
CH2), 7.15e7.18 (m, 3H, ArH), 7.18 (dd, J¼7.5, 6.4 Hz, 2H, ArH), 7.71
(dd, J¼5.5, 3.1 Hz, 2H, ArH), 7.84 (dd, J¼5.5, 3.1 Hz, 2H, ArH). 13C
4.3.9. S-1-Acetoxy-4-phthalimidobutan-2-yl O-ethyl dithiocarbonate
(3j).21 The reactionwas complete after addition of 6.25 mol % of DLP.
Yellow oil; yield: 641 mg, 84%. 1H NMR (CDCl3, 400 MHz) (
d, ppm)
1.40 (t, J¼7.1 Hz, 3H, CH3), 2.08 (s, 3H, CH3), 2.05 (dddd, J¼14.1, 7.7,
7.2, 6.8 Hz, 1H in CH2), 2.19 (dddd, J¼14.1, 7.2, 6.8, 6.8 Hz, 1H in CH2),
3.83(ddd, J¼13.9, 7.2, 7.2Hz,1H in CH2), 3.88 (ddd, J¼13.9, 6.8, 6.8 Hz,
1H in CH2), 3.99 (dddd, J¼6.9, 6.9, 5.7, 4.7 Hz, 1H, CH), 4.28 (dd,
J¼11.5, 5.7 Hz,1H in CH2), 4.42 (dd, J¼11.5, 4.7 Hz,1H in CH2), 4.62 (q,
J¼7.1 Hz, 2H, CH2), 7.73 (dd, J¼5.5, 3.1 Hz, 2H, ArH), 7.85 (dd, J¼5.5,
NMR (CDCl3, 100 MHz) (d, ppm) 13.7, 28.4, 33.1, 33.4, 35.5, 35.6,
48.6, 69.8, 123.2, 125.8, 128.2, 128.3, 132.1, 133.9, 141.8, 168.2, 214.0.
IR (nmax, cmꢁ1) 3060, 3025, 1772, 1712, 1217, 1050. HRMS (ESI) calcd
for C23H26NO3S2 [MþH]þ m/z 428.1354; found 428.1349.
3.1 Hz, 2H, ArH). 13C NMR (CDCl3, 100 MHz) (
d, ppm) 13.6, 20.7, 29.7,
35.5, 46.9, 65.0, 70.2, 123.2, 132.0, 134.0, 168.1, 170.5, 212.6.
4.3.10. S-1-Acetylthio-4-phthalimidobutan-2-yl O-ethyl dithiocar-
bonate (3k). The reaction was complete after addition of 25 mol %
of DLP. Pale yellow solid; mp: 59e61 ꢀC; yield: 310 mg, 39%. 1H NMR
4.3.5. O-Ethyl S-5-phenyl-1-phthalimidopentan-3-yl dithiocarbonate
(3e). The reaction was complete after addition of 17.5 mol % of DLP.
Yellow oil; yield: 686 mg, 83%. 1H NMR (CDCl3, 400 MHz) (
d, ppm)
(CDCl3, 400 MHz) (
J¼14.2, 7.7, 6.8, 6.8 Hz,1H in CH2), 2.14 (dddd, J¼14.2, 7.7, 6.4, 6.4 Hz,
d
, ppm) 1.40 (t, J¼7.1 Hz, 3H, CH3), 2.03 (dddd,
1.37 (t, J¼7.1 Hz, 3H, CH3), 1.98 (dddd, J¼14.4, 7.3, 7.1, 6.9 Hz, 1H in
CH2), 2.08e2.18 (m, 3H, 1H in CH2 & CH2), 2.72 (ddd, J¼13.6, 10.0,