P.R. Krishna et al. / Tetrahedron 69 (2013) 2319e2326
2325
J¼6.9 Hz, eCHCOOR), 3.61 (1H, t, J¼6.5 Hz, eCHaHbOH), 3.47 (1H, t,
J¼6.5 Hz, eCHaHbOH), 1.71e1.65 (1H, m, eCHaHb), 1.64e1.53 (3H,
m, eCHaHb, eCH2), 1.51 (3H, d, J¼6.9 Hz, eCH3); 13C NMR (CDCl3,
75 MHz): 173.8, 140.6, 136.2, 128.5, 127.5, 127.1, 116.7, 74.5, 62.2,
45.7, 30.2, 27.8, 18.2; MS (ESI) m/z 271 [MþNa]þ.
evaporated and the residue purified by column chromatography
(silica gel, 60e120 mesh, Rf 0.50, 10% EtOAc/hexane) to furnish 12
(0.78 g, 82%) as a colorless oil. Found: C, 61.09; H, 10.92; Si, 10.07.
C14H30O3Si requires C, 61.26; H, 11.02; Si, 10.23%; [
CHCl3); IR (neat)
1217, 1159, 1059 cmꢁ1
a
]
25 þ139.7 (c 0.3,
D
n
: 3047, 2986, 2934, 1794, 1745, 1645, 1454, 1373,
;
1H NMR (CDCl3, 500 MHz): 5.72e5.62 (1H,
4.13. (R)-((R)-6-Azidohex-1-en-3-yl)-2-phenylpropanoate 2a
m, olefinic-H), 5.23e5.14 (2H, m, olefinic-H), 4.70 (1H, d, J¼6.1 Hz,
eCHaHbOMe), 4.54 (1H, d, J¼5.5 Hz, eCHaHbOMe), 4.03e3.96 (1H,
m, eCHOMOM), 3.67e3.59 (2H, m, eCH2OTBS), 3.37 (3H, s, eOMe),
1.68e1.52 (m, 4H), 0.89 (s, 9H), 0.05 (s, 6H); 13C NMR (CDCl3,
75 MHz): 138.1, 117.0, 93.5, 76.4, 62.8, 55.2, 31.5, 28.5, 25.8, 18.1,
ꢁ5.5; MS (ESI) m/z 297 [MþNa]þ.
Adopted the same procedure as described for the synthesis com-
pound 2 and purified by column chromatography (silica gel, 60e120
mesh, Rf 0.80, 3% EtOAc/hexane). Compound 10a (0.37 g, 1.49 mmol)
gave 2a (0.27 g, 66% over two steps) as a colorless syrup. Found: C,
65.72; H, 6.89; N, 15.16. C15H19N3O2 requires C, 65.91; H, 7.01; N,
15.37%; [
a
]
25 ꢁ88.5 (c 0.3, CHCl3); IR (neat)
n
: 3029, 2982, 2174, 1745,
7.39e7.23 (5H, m,
4.17. (R)-4-(Methoxymethoxy)hex-5-en-1-ol 13
D
1638,1584, 704 cmꢁ1; 1H NMR (CDCl3, 300 MHz):
d
AreH), 5.84e5.75 (1H, m, olefinic-H), 5.32e5.21 (2H, m, olefinic-H),
5.00e4.99 (1H, m, eCHOCOR), 3.72 (1H, q, J¼6.9 Hz, eCHCOOR), 3.25
(1H, t, J¼6.2 Hz, eCHaHbN3), 3.09 (1H, t, J¼6.6 Hz, eCHaHbN3),
1.78e1.54 (4H, m, eCH2), 1.50 (3H, d, J¼6.9 Hz, eCH3); 13C NMR
(CDCl3, 75 MHz): 173.6, 140.5, 135.9, 128.5, 127.4, 127.3, 116.6, 74.1,
50.9, 45.5, 31.0, 24.2, 18.3; MS (ESI) m/z 296 [MþNa]þ.
Adopted the same procedure as described for the synthesis
compound 10 and purified by column chromatography (silica gel,
60e120 mesh, Rf 0.40, 20% EtOAc/hexane). Compound 12 (0.75 g,
2.74 mmol) gave 13 (0.306 g, 70%) as a thick syrup. Found: C, 59.82;
25
H, 9.94. C8H16O3 requires C, 59.97; H, 10.07%; [
CHCl3); IR (neat)
1034, 916 cmꢁ1
a
]
þ227.6 (c 0.2,
D
n
: 3416, 2935, 1711, 1608, 1514, 1441, 1252, 1101,
;
1H NMR (CDCl3, 300 MHz): 5.74e5.65 (1H, m,
4.14. (R)-Methyl-5-azido-2-((R)-2-phenylpropanoyloxy)pen-
tanoate 11a
olefinic-H), 5.25e5.18 (2H, m, olefinic-H), 4.71 (1H, d, J¼6.6 Hz,
eCHaHbOMe), 4.55 (1H, d, J¼6.6 Hz, eCHaHbOMe), 4.07e4.00 (1H,
m, eCHeOMOM), 3.67 (2H, t, J¼5.5 Hz, eCH2OH), 3.38 (3H, s,
eOMe), 1.73e1.55 (4H, m, eCH2); 13C NMR (CDCl3, 75 MHz): 138.1,
117.0, 93.5, 76.4, 63.2, 55.2, 31.5, 27.6; MS (ESI) m/z 183 [MþNa]þ.
Adopted the same procedure as described for the synthesis
compound 11 and purified by column chromatography (silica gel,
60e120 mesh, Rf 0.50, 7% EtOAc/hexane). Compound 2a (0.24 g,
0.88 mmol) gave 11a (0.21 g, 78% over two steps) as a colorless
4.18. (R)-6-Azido-3-(methoxymethoxy)hex-1-ene 14
liquid. Found: C, 58.94; H, 6.18; N, 13.56. C15H19N3O4 requires C,
25
59.01; H, 6.27; N, 13.76%; [
a
]
D
þ74.6 (c 0.2, CHCl3); IR (neat)
n
:
Adopted the same procedure as described for the synthesis
compound 2 and purified by column chromatography (silica gel,
60e120 mesh, Rf 0.60, 4% EtOAc/hexane). Compound 13 (0.28 g,
1.75 mmol) gave 14 (0.232 g, 71% over two steps) as a colorless
3068, 2994, 2185, 1725, 1589, 784 cmꢁ1; 1H NMR (CDCl3, 300 MHz):
7.36e7.28 (3H, m, AreH), 7.27e7.23 (2H, m, AreH), 5.00 (1H, dd,
J¼7.5 Hz, 4.5 Hz, eCHOCOR), 3.83 (1H, q, J¼6.9 Hz, eCHCOOR), 3.74
(3H, s, eOMe), 3.24 (1H, t, J¼6.5 Hz, eCHaHbNH), 3.16e3.10 (1H, m,
eCHaHbNH), 1.95e1.79 (4H, m, eCH2), 1.54 (3H, d, J¼7.9 Hz, eCH3);
13C NMR (CDCl3, 75 MHz): 173.9, 170.2, 140.0, 128.6, 127.5, 127.3,
71.6, 52.4, 50.5, 45.1, 28.1, 24.4, 18.2; MS (ESI) m/z 328 [MþNa]þ.
liquid. Found C, 51.71; H, 8.01; N, 22.51. C8H15N3O2 requires C,
25
51.88; H, 8.16; N, 22.69%; [
a
]
D
þ256.8 (c 0.3, CHCl3); IR (neat)
n
:
3081, 2987, 2194, 2143, 1595, 1054 cmꢁ1
;
1H NMR (CDCl3,
500 MHz): 5.74e5.60 (1H, m, Olefinic-H), 5.27e5.17 (2H, m, ole-
finic-H), 4.70 (1H, d, J¼6.8 Hz, eCHaHbOMe), 4.54 (1H, d, J¼6.7 Hz,
eCHaHbOMe), 4.06e3.97 (1H, m, eCHeOMOM), 3.38 (3H, s,
4.15. (R)-((R)-2-Oxopiperidin-3-yl)-2-phenylpropanoate 1a
eOMe), 3.31 (2H, t, J¼6.4 Hz, eCH2N3),1.79e1.53 (4H, m, eCH2); 13
C
Adopted the same procedure as described for the synthesis
compound 1 and purified by column chromatography (silica gel,
60e120 mesh, Rf 0.7, 2% MeOH/CHCl3). Compound 11a (0.18 g,
NMR (CDCl3, 75 MHz): 137.8, 117.5, 93.7, 76.7, 55.5, 51.3, 32.4, 24.8;
MS (ESI) m/z 208 [MþNa]þ.
0.59 mmol) gave 1a (0.094 g, 64%) as a semi solid. Found: C, 67.93;
4.19. (R)-Methyl-5-azido-2-(methoxymethoxy)pentanoate 15
25
H, 6.82; N, 5.61. C14H17NO3 requires C, 68.00; H, 6.93; N, 5.66%; [a]
D
25
þ23.5 (c 0.3, MeOH) (lit.1 [
a]
ꢁ100.5 (c 0.5, MeOH)); IR (neat)
n
:
Adopted the same procedure as described for the synthesis
compound 11 and purified by column chromatography (silica gel,
60e120 mesh, Rf 0.40, 12% EtOAc/hexane). Compound 14 (0.20 g,
1.08 mmol) gave 15 (0.17 g, 72% over two steps) as a thick syrup.
Found: C, 44.14; H, 6.88; N, 19.29. C8H15N3O4 requires C, 44.23; H,
D
3209, 3065, 2946, 2853, 1737, 1662, 1571, 1312, 1089, 707 cmꢁ1; 1H
NMR (CDCl3, 500 MHz): 7.36e7.30 (2H, m, AreH), 7.27e7.22 (3H, m,
AreH), 6.06 (1H, br s, eNH), 5.24 (1H, dd, J¼8.9, 6.5 Hz, eCH(OCO)
CONH), 3.82 (1H, q, J¼6.9 Hz, eCHCOOR), 3.32e3.24 (2H, m,
eCH2NH), 2.14e2.05 (1H, m, eCHaHbCH2NH), 2.04e1.98 (1H, m,
eCHaHbCH(OCO)CONH), 1.96e1.88 (1H, m, eCHaHbCH2NH),
1.83e1.74 (1H, m, eCHaHbCH(OCO)CONH), 1.52 (3H, d, J¼6.9 Hz,
eCH3); 13C NMR (CDCl3, 150 MHz): 173.7, 168.9, 140.5, 128.6, 127.4,
127.1, 68.7, 45.2, 42.1, 26.7, 19.9, 18.5; MS (ESI) m/z 270 [MþNa]þ.
6.96; N, 19.34%; [
a
]
25 ꢁ238.6 (c 0.4, CHCl3); IR (neat)
n
: 2982, 2194,
D
1725,1595,1145 cmꢁ1; 1H NMR(CDCl3, 300 MHz): 4.69 (2H, 2ꢂd, AB
pattern, J¼7.2 Hz, eCH2OMe), 4.19e4.13 (1H, m, eCH(OMOM)
COOMe), 3.76 (3H, s, eOMe), 3.40 (3H, s, eOMe), 3.33 (2H, t,
J¼6.8 Hz, eCH2N3), 1.91e1.80 (1H, m, eCH2), 1.79e1.54 (3H, m,
eCH2); 13C NMR (CDCl3, 75 MHz): 172.6, 96.1, 74.7, 55.9, 51.9, 50.9,
29.8, 24.6; MS (ESI) m/z 240 [MþNa]þ.
4.16. (R)-10,10,11,11-Tetramethyl-5-vinyl-2,4,9-trioxa-10-
siladodecane 12
4.20. (R)-3-(Methoxymethoxy)piperidin-2-one 16
To a stirred solution of 4 (0.80 g, 3.48 mmol) in CH2Cl2 (8 mL),
DIPEA (1.38 mL, 10.44 mmol), methoxymethyl chloride (0.45 mL,
5.22 mmol), and DMAP (cat.), were added at 0 ꢀC and stirred at
room temperature for 6 h. Reaction mixture was extracted with
CH2Cl2 (2ꢂ15 mL), and combined organic layers were washed with
water (12 mL), brine (12 mL) and dried (Na2SO4). Solvent was
Adopted the same procedure as described for the synthesis
compound 1 and purified by column chromatography (silica gel,
60e120 mesh, Rf 0.70, 2% MeOH/CH2Cl2). Compound 15 (0.14 g,
0.65 mmol) gave 16 (0.085 g, 82%) as a sticky oil. Found: C, 52.77; H,
25
8.17; N, 8.72. C7H13NO3 requires C, 52.82; H, 8.23; N, 8.80%; [a]
D