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4.6.1. (1S,2R,3S,4S)-[2-Benzyloxy-4-(2-(methoxy)ethoxy-
methoxy)-3-trityloxymethyl]cyclopentanol 26b)
(MEMOCHCH2), 38.2 (TrOCH2CHCH2). ES+ m/z (%) 485 ((M+Na)+,
100). HRMS (ES+) for C29H34O5Na (M+Na)+: Calcd 485.2298; Mea-
sured 485.2291.
Starting from 22b (28.0 mg), yield: 99% (23.0 mg, clear oil);
HPLC (acetone/hexane 35:65). Data: [
27 °C). IR 3467 (w,br), 3058 (w), 2878 (m), 1490 (m), 1449 (m),
1090 (s), 1045 (s) cmꢁ1 1H NMR (400 MHz, CDCl3) 7.45–7.24
a
]
+16.5 (c 0.65, CHCl3,
D
4.6.4. (1R,2S,3R,4S)-[2-Acetoxymethyl-3-benzyloxy-4-hydroxy]-
cyclopent-1-yl acetate 28b
.
(15H, m, ArH), 4.70 (1H, d, J = 11.0 Hz, OCHaHbO), 4.69 (1H, d,
J = 11.0 Hz, OCHaHbO), 4.56 (1H, d, J = 12.0 Hz, CHaHbPh), 4.55
(1H, d, J = 12.0 Hz, CHaHbPh), 4.13 (1H, quintet, J = 5.0 Hz, CHOH),
4.07 (1H, ddd, J = 7.5, 5.5, 5.0 Hz, CHOMEM), 3.80 (1H, dd, J = 7.5,
5.0 Hz, CHOBn), 3.68 (1H, ddd, J = 11.0, 5.5, 4.5 Hz, OCHaHbCH2O),
3.59 (1H, ddd, J = 11.0, 5.0, 4.5 Hz, OCHaHbCH2O), 3.50–3.47 (2H,
m, OCH2CH2O), 3.38 (3H, s, OMe), 3.31 (1H, dd, J = 9.5, 4.5 Hz,
CHaHbOTr), 3.28 (1H, dd, J = 9.5, 4.5 Hz, CHaHbOTr), 2.58 (1H, d,
J = 5.0 Hz, OH), 2.40 (1H, m, CHCH2OTr), 2.20 (1H, ddd, J = 14.0,
7.5, 5.0 Hz , CHaHbCHOH), 1.94 (1H, dt, J = 14.0, 4.5 Hz, CHaHb-
CHOH). 13C NMR (100 MHz, CDCl3) 144.1 (CAr ꢂ 3), 138.1 (CAr),
128.9 (CHAr ꢂ 6), 128.6 (CHAr ꢂ 2), 127.93 (CHAr ꢂ 6), 127.88
(CHAr ꢂ 3) 127.2 (CHAr ꢂ 3), 94.9 (OCH2O), 86.7 (CPh3), 81.6
(CHOBn), 76.5 (CHOMEM), 72.0 and 71.8 (CH2Ph + OCH2CH2O),
70.3 (CHOH), 67.0 (OCH2CH2O), 61.8 (CH2OTr), 59.1 (OCH3), 50.3
(CHCH2OTr), 38.3 (CH2CHOH). ES+ m/z (%) 591 ((M+Na)+, 100).
HRMS (ES+) for C36H40O6Na (M+Na)+: Calcd 591.2717; Measured
591.2707.
Starting from 24b (25.0 mg), yield: 92% (17.0 mg, clear oil);
HPLC (acetone/hexane 35:65). Data: [
27 °C). IR 3501 (m,br), 2944 (w), 1735 (s), 1455 (w), 1364 (m),
1243 (s) cmꢁ1 1H NMR (400 MHz, CDCl3) 7.39–7.30 (5H, m, ArH),
a]D = +23.6 (c 0.55, CHCl3,
.
4.90 (1H, ddd, J = 8.5, 6.5, 4.0 Hz, CHOAc), 4.64 (1H, d, J = 12.0 Hz,
CHaHbPh), 4.56 (1H, d, J = 12.0 Hz, CHaHbPh), 4.20–4.19 (2H, m,
CH2OAc), 4.13 (1H, m, CHOH), 3.61 (1H, dd, J = 9.0, 4.5 Hz, CHOBn),
2.55 (1H, ddt, J = 9.0, 6.5, 4.5 Hz, CHCH2OAc), 2.46 (1H, dd, J = 3.0,
1.0 Hz, OH), 2.26 (1H, dddd, J = 15.5, 8.5, 5.0, 1.0 Hz, CHaHbCHOH),
2.05 (3H, s, COCH3), 1.98 (3H, s, COCH3), 1.85 (1H, s, CHaHbCHOH).
13C NMR (100 MHz, CDCl3) 171.0 (C@O), 170.9 (C@O), 137.6 (CAr),
128.8 (CHAr ꢂ 2), 128.4 (CHAr), 128.1 (CHAr ꢂ 2), 80.5 (CHOBn),
72.7 (CHOAc), 72.4 (CH2Ph), 69.4 (CHOH), 62.4 (CH2OAc), 47.3
(CHCH2OAc), 37.7 (CH2CHOH), 21.2 (COCH3), 20.9 (COCH3). ES+
m/z (%) 345 ((M+Na)+, 100). HRMS (ES+) for C17H22O6Na (M+Na)+:
Calcd 345.1309; Measured 345.1316.
4.6.5. (1R,2S,3S,4S)-[2-Acetoxymethyl-3-benzyloxy-4-hydroxy]-
cyclopent-1-yl acetate 28a
4.6.2. (1S,2S,3S,4S)-[2-Benzyloxy-4-(2-(methoxy)ethoxy-
methoxy)-3-trityloxymethyl]cyclopentanol 26a
Starting from 24a (19.0 mg), yield: 93% (13.0 mg, clear oil). Data:
[a]
D = ꢁ55.7 (c 0.45, CHCl3, 28 °C). IR 3464 (m,br), 2940 (m,br), 1736
Starting from 22a (23.6 mg), yield: 84% (16.5 mg, clear oil);
(s), 1367 (m), 1241 (s) cmꢁ1 1H NMR (400 MHz, CDCl3) 7.37–7.27
.
HPLC (acetone/hexane 36:64). Data: [
26 °C). IR 3440 (m,br), 3059 (w), 2931 (m), 2885 (m), 1490 (m),
1449 (m), 1041 (s) cmꢁ1 1H NMR (400 MHz, CDCl3) 7.42–7.19
a
]
D = +16.9 (c 0.54, CHCl3,
(5H, m, ArH), 5.06 (1H, ddd, J = 8.5, 7.0, 4.0 Hz, CHOAc), 4.60 (1H, d,
J = 12.0 Hz, CHaHbPh), 4.52 (1H, d, J = 12.0 Hz, CHaHbPh), 4.31 (1H,
dd, J = 11.0, 8.0 Hz, CHaHbOAc), 4.27 (1H, m, CHOH), 4.23 (1H, dd,
J = 11.0, 6.5 Hz, CHaHbOAc), 3.90 (1H, m, CHOBn), 2.74–2.64 (2H,
m, CHCH2OAc + CHaHbCHOH), 2.05 (3H, s, COCH3), 2.00 (3H, s,
.
(20H, m, ArH), 4.63 (1H, d, J = 7.0 Hz, OCHaHbO), 4.56 (1H, d,
J = 7.0 Hz, OCHaHbO), 4.55 (1H, d, J = 12.5 Hz, CHaHbPh), 4.51 (1H,
d, J = 12.5 Hz, CHaHbPh), 4.38–4.32 (2H, m, CHOH + CHOMEM),
3.82 (1H, dd, J = 6.5, 3.0 Hz, CHOBn), 3.57 (1H, dt, J = 11.0, 5.0 Hz,
OCHaHbCH2O), 3.50-3.35 (5H, m, OCHaHbCH2O + OCH2CH2O +
CH2OTr), 3.34 (3H, s, OCH3), 2.60 (1H, quintet, J = 6.5 Hz,
CHCH2OTr), 2.23 (1H, ddd, J = 14.5, 7.0, 3.5 Hz , CHaHbCHOH),
1.82 (1H, ddd, J = 14.5, 6.0, 5.0 Hz, CHaHbCHOH), 1.42 (1H, d,
J = 3.5 Hz, OH). 13C NMR (100 MHz, CDCl3) 144.5 (CAr ꢂ 3), 138.8
(CAr), 128.9 (CHAr ꢂ 6), 128.4 (CHAr ꢂ 2), 127.83 (CHAr ꢂ 6),
127.76 (CHAr ꢂ 2), 127.6 (CHAr), 127.0 (CHAr ꢂ 3), 94.9 (OCH2O),
87.0 (CPh3), 85.9 (CHOBn), 77.1 and 76.9 (CHOMEM + CHOH),
72.3 (CH2Ph), 71.8 (OCH2CH2O), 66.8 (OCH2CH2O), 59.3 (CH2OTr),
59.1 (OCH3), 46.3 (CHCH2OTr), 40.5 (CH2CHOH). ES+ m/z (%) 591
((M+Na)+, 100). HRMS (ES+) for C36H40O6Na (M+Na)+: Calcd
591.2717; Measured 591.2727.
COCH3), 1.82 (1H, d, J = 4.5 Hz, OH), 1.61 (1H, m, CHaHbCHOH). 13
C
NMR (100 MHz, CDCl3) 171.0 (C@O), 170.8 (C@O), 138.1 (CAr),
128.6 (CHAr ꢂ 2), 128.0 (CHAr), 127.8 (CHAr ꢂ 2), 84.4 (CHOBn),
75.6 (CHOAc), 74.2 (CHOH), 72.3 (CH2Ph), 61.7 (CH2OAc), 46.3
(CHCH2OAc), 39.2 (CH2CHOH), 21.3 (COCH3), 21.0 (COCH3). ES+ m/z
(%) 345 ((M+Na)+, 100). HRMS (ES+) for C17H22O6Na (M+Na)+: Calcd
345.1309; Measured 345.1316.
4.6.6. (1R,2S,4R)-[2-Acetoxymethyl-4-hydroxy]cyclopent-1-yl
acetate 29
Starting from 25 (13.7 mg), yield: 86% (7.7 mg, clear oil); HPLC
(acetone/hexane 36:64). Data: [
IR 3450 (m,br), 2943 (m,br), 1732 (vs), 1367 (m), 1238 (vs), 1046
(m) cmꢁ1 1H NMR (400 MHz, CDCl3) 5.00 (1H, ddd, J = 8.0, 5.5,
a
]D = ꢁ40.0 (c 0.34, CHCl3, 26 °C).
.
4.0 Hz, CHOAc), 4.38 (1H, qt, J = 5.5, 2.5 Hz, CHOH), 4.11–4.09
(2H, m, CH2OAc), 2.66 (1H, ddq, J = 9.5, 8.0, 5.5 Hz, CHCH2OAc),
2.34 (1H, ddd, J = 15.0, 7.5, 5.5 Hz, AcOCHCHaHb), 2.07 (3H, s,
COCH3), 2.06 (3H, s, COCH3), 1.99 (1H, ddt, J = 14.0, 8.0, 2.5 Hz,
AcOCH2CHCHaHb), 1.77 (1H, ddt, J = 15.0, 4.0, 2.5 Hz, AcOCHCHaHb),
1.68 (1H, d, J = 5.5 Hz, OH), 1.63 (1H, ddd, J = 14.0, 9.5, 5.5 Hz,
AcOCH2CHCHaHb). 13C NMR (100 MHz, CDCl3) 171.1 (C@O), 170.8
(C@O), 77.0 (CHOAc), 72.1 (CHOH), 65.2 (CH2OAc), 43.2
(CHCH2OAc), 41.8 (AcOCHCH2), 37.7 (AcOCH2CHCH2), 21.4
(COCH3), 21.0 (COCH3). ES+ m/z (%) 239 ((M+Na)+, 100). HRMS
(ES+) for C10H16O5Na (M+Na)+: Calcd 239.0889; Measured
239.0888.
4.6.3. (1R,3S,4S)-[4-(2-(Methoxy)ethoxymethoxy)-3-trityloxym-
ethyl]cyclopentanol 27
Starting from 23 (18.7 mg), yield: 91% (13.7 mg, clear oil); HPLC
(acetone/hexane 4:6). Data: [
3441 (m,br), 3057 (w), 2928 (m), 1490 (m), 1449 (m), 1045 (s)
cmꢁ1 1H NMR (400 MHz, CDCl3) 7.44–7.21 (15H, m, ArH), 4.75
a]D = +2.9 (c 0.60, CHCl3, 26 °C). IR
.
(1H, d, J = 7.0 Hz, OCHaHbO), 4.73 (1H, d, J = 7.0 Hz, OCHaHbO),
4.26 (1H, m, CHOH), 4.15 (1H, dt, J = 5.5, 3.5 Hz, CHOMEM), 3.70
(1H, m, OCHaHbCH2O), 3.63 (1H, dt, J = 11.0, 4.5 Hz, OCHaHbCH2O),
3.50 (2H, app t, J = 4.5 Hz, OCH2CH2O), 3.37 (3H, s, OCH3), 3.08 (1H,
dd, J = 9.0, 6.0 Hz, CHaHbOTr), 2.97 (1H, dd, J = 9.0, 7.0 Hz, CHaH-
bOTr), 2.57 (1H, m, CHCH2OTr), 2.28 (1H, d, J = 7.0 Hz, OH), 2.00
(1H, ddt, J = 14.0, 8.5, 2.0 Hz, TrOCH2CHCHaHb), 1.94–1.84 (2H, m,
MEMOCHCH2), 1.56 (1H, ddd, J = 14.0, 8.0, 5.5 Hz, TrOCH2CH-
CHaHb). 13C NMR (100 MHz, CDCl3) 144.3 (CAr ꢂ 3), 128.9
(CHAr ꢂ 6), 127.9 (CHAr ꢂ 6), 127.1 (CHAr ꢂ 3), 94.4 (OCH2O), 86.6
(CPh3), 80.8 (CHOMEM), 73.4 (CHOH), 71.9 (OCH2CH2O), 67.1
(OCH2CH2O), 65.1 (CH2OTr), 59.1 (OCH3), 45.1 (CHCH2OTr), 41.1
Acknowledgements
L.M.H.L. thanks CMS Chemicals and SEEDA/EPSRC for a student-
ship. Dr A. James Boydell is thanked for obtaining the characterisa-
tion data for compound 9. We also wish to acknowledge the use of
the EPSRC’s Chemical Database service at Daresbury.34