Macromolecules
ARTICLE
using a Perkin-Elmer DSC Pyris 1. Samples were run under a nitro-
(m, 3H, CH
3
ꢀPEGꢀ), 3.09 (s, 1H), 2.75 (dd, J = 14.0 Hz, J = 4.9 Hz,
gen atmosphere from ꢀ10 to 100 °C with a heating/cooling rate of
1H), 2.63 (d, J = 4.7 Hz, 1H), 1.78 (m, 1H) (dd, J = 11.6 Hz, J = 1.5 Hz,
1H), 1.69 (d, J = 6.7 Hz, 3H, CH
ꢀ
1
1
(
0 °C min . Dialysis membrane Spectra/Por 6, MWCO 1000 and 3500
3
ꢀ of LA unit), 1.54 (dd, J = 14.1 Hz,
13
38 mm flat width), was purchased from SpectrumLabs and rinsed with
J = 3.6 Hz, 1H), 1.26ꢀ1.23 (m, 1H). C NMR (CDCl
3
, 100 MHz, data
water prior to use. About 10 cm of dialysis membrane was used per puri-
fication. For 4c and polymers 5aꢀc, a dichloromethane solution of pro-
duct was introduced inside the dialysis bag (MWCO 1000 for macro-
monomer 4c and polymers 5a,b and MWCO 3500 for polymer 5c) that
was then introduced to 0.5 L of dichloromethane and gently stirred for
about 12 h. Four cycles were performed for each dialysis.
shown for major isomer): δ = 167.9, 167.1, 85.7, 78.7, 73.0, 72.1, 70.8, 70.7
+
(x2), 70.2, 62.7, 59.2, 48.9, 48.3, 41.0, 38.2. 31.5, 16.7. MS-ESI (M + H)
m/z calcd for C26 11 574.63; found 574.2. Elemental analysis:
calcd for C26H N O11: C 54.44, H 7.56, N 7.33; found: C 54.85, H 7.76,
N 7.12. IR (KBr) ν (cm ): 2922.3, 2870.3, 2105.6, 1957.5, 1757.7,
1466.3, 1350.9, 1282.0, 1140.8, 1062.6, 986.7, 937.0, 851.7, 743.7, 685.7,
649.0, 571.1.
44 3
H N O
43 3
ꢀ
1
Single Crystal Structure Determination. A colorless block
3
2
crystal 4d with the size of 0.12 ꢁ 0.22 ꢁ 0.30 mm was selected for geo-
Synthesis of Poly(ethylene glycol methyl ether)ꢀ1,2,3-Δ -
0
metry and intensity data collection with a Bruker SMART APEXII CCD
area detector on a D8 goniometer at 100 K. The temperature during the
data collection was controlled with an Oxford Cryosystems Series
Triazoline-spiro[6-methyl-1,4-dioxane-2,5-dione-3,2 -bicyclo-
[2.2.1]heptane] (M
∼ 2200), PEG40ꢀSpirolactide (4c). Azido-
n
poly(ethylene glycol methyl ether) (M
w
∼ 2000), PEG40-N
3
, 3c (3.35 g,
0
700 plus instrument. Preliminary lattice parameters and orientation matrices
1.67 mmol), and spiro[6-methyl-1,4-dioxane-2,5-dione-3,2 -bicyclo[2.2.1]
hepta-5-ene], 2 (1.26 mg, 6.0 mmol, 3.6 equiv), were dissolved in EtOAc
(40 mL). The reaction was refluxed under nitrogen for 3 days. The crude
reaction was concentrated under reduced pressure to afford a dark green
were obtained from three sets of frames. Data were collected using
graphite-monochromated and 0.5 mm MonoCap-collimated Mo Kα ra-
27
diation (λ = 0.710 73 Å) with the ω scan method. Data were processed
27
with the INTEGRATE program of the APEX2 software for reduction
and cell refinement. Multiscan absorption corrections were applied by
using the SCALE program for area detector. The structure was solved by
solid. The crude product was dissolved in CH
Cl
2 2
(∼15 mL), and diethyl
ether was added (∼30 mL). The suspension was refluxed for 20 min and
cooled down to room temperature, affording a white suspension and a
green oil. The layers were separated, and the white suspension was cooled
down to 4 °C when a white solid precipitated. This solid was washed with
diethyl ether. The crystallyzation was repeated two more times, affording
the title compound as a white solid (1.17 g, 32%). The monomer was dial-
2
28
the direct method and refined on F (SHELXTL). Non-hydrogen
atoms were refined with anisotropicdisplacementparameters, andhydro-
gen atoms on carbons were placed in idealized positions (CꢀH = 0.99 or
1
.00 Å) and included as riding with U (H) = 1.2 or 1.5 U (non-H).
iso eq
2
2 2
yzedin CH Cl using a cellulose membrane (MWCO 1000). Finally, com-
Synthesis of Triethylene Glycol Methyl Etherꢀ1,2,3-Δ -
0
pound 4c was lyophilized twice from distilled benzene (3 times distilled)
prior to polymerization. H NMR (CDCl , 400 MHz, data shown for
3
Triazoline-spiro[6-methyl-1,4-dioxane-2,5-dione-3,2 -bicyclo-
[
1
2.2.1]heptane], PEG -Spirolactide (4a). Azidotriethylene glycol
3
methyl ether, PEG -N , 3a (684 mg, 3.62 mmol), and spiro[6-methyl-
major isomer): δ = 5.17 (q, J = 6.6 Hz, 1H, ꢀCHꢀ of LAunit), 4.92 (d, J =
3
3
0
1,4-dioxane-2,5-dione-3,2 -bicyclo[2.2.1]hepta-5-ene], 2 (753 mg, 3.62
9.7 Hz, 1H, ꢀCHꢀ of triazoline unit), 3.73ꢀ3.45 (PEG chain), 3.45 (m,
mmol), were dissolved in EtOAc (20 mL). The reaction was refluxed
3H), 3.36 (m, 3H, CH
3
ꢀPEGꢀ), 3.08 (s, 1H), 2.75 (dd, J = 14.0 Hz, J =
1
under nitrogen for3 days, andtheconversion was monitored by H NMR
4.9 Hz, 1H), 2.62 (d, J = 4.6 Hz, 1H), 1.87 (dd, J = 11.6 Hz, J =1.3 Hz, 1H),
1.68 (d, J =6.7Hz, 3H, CH
ꢀ of LAunit), 1.53 (dd, J= 14.1 Hz, J=3.7 Hz,
1H), 1.24 (m, 1H). C NMR (CDCl , 100 MHz, data shown for major
spectroscopy. The crude reaction was concentrated under reduced pres-
sure to give a brown oil. This crude product was purified by silica chroma-
3
1
3
3
tography using EtOAc/hexane 7:3 as eluent to afford the titled triazoline
isomer): δ = 167.9, 167.0, 88.6, 85.7, 78.7, 77.4, 70.3 (PEG chain), 62.7,
59.2, 56,1, 49.0, 48.3, 44.9, 41.0, 40.0, 39.5, 38.3, 31.6, 27.3, 16.8. Melting
1
3
as a yellow oil (897 mg, 62%). H NMR (CDCl , 400 MHz, data shown
for major isomer): δ = 5.18 (q, J = 4.9 Hz, 1H, ꢀCHꢀ of LA unit), 4.92
point: 45ꢀ46 °C. Elemental analysis: calcd for C94
H N O45: C 53.55, H
218 3
ꢀ
1
(
d, J = 9.8 Hz, 1H, ꢀCHꢀ of triazoline unit), 3.81 (m, 2H), 3.75ꢀ3.60
PEG chain, 12H), 3.57 (m, 3H), 3.37 (s, 3H, CH
ꢀPEGꢀ), 3.08 (s,
H), 2.76 (dd, J = 14.3 Hz, J = 5.0 Hz 1H), 2.63 (d, J = 4.9 Hz, 1H), 1.76
10.3, N 2.0; found: C 53.79, H 8.61, N 1.08. IR (KBr) ν (cm ): 2921.3,
2882.4, 2242.3, 2098.6, 2058.5, 1954.3, 1758.6, 1467.0, 1343.2, 1280.6,
1241.9, 1112.8, 963.0, 843.0, 742.8, 569.8.
(
3
1
2
(
dt, J = 11.7 Hz, J = 1.5 Hz, 1H), 1.69 (d, J = 6.7 Hz, 3H, CH ꢀ of LA
Synthesis of Adamantyl-1,2,3-Δ -triazolineꢀSpiro[6-meth-
3
1
3
0
unit), 1.53 (dd, J = 14.1 Hz, J = 3.5 Hz, 1H), 1.28ꢀ1.25 (m, 1H).
C
yl-1,4-dioxane-2,5-dione-3,2 -bicyclo[2.2.1]heptane] (4d). 1-
NMR (CDCl
3
, 100 MHz, data shown for major isomer): δ = 167.9,
Azidoadamantante (255 mg, 1.44 mmol) and spiro[6-methyl-1,4-diox-
0
1
3
67.1, 85.7, 78.7, 73.0, 72.1, 70.8 (ꢁ2), 70.7, 70.3, 62.7, 59.2, 49.0, 48.3,
ane-2,5-dione-3,2 -bicyclo[2.2.1]hepta-5-ene], 2 (300 mg, 1.44 mmol),
+
+
+
8.3, 31.6, 16.8. ESI-mass: 420.1 (M +Na ). MS-ESI (M + H) m/z
398.42; found 398.1. Elemental analysis: calcd for
: C 54.40, H 6.85, N 10.57; found: C 54.78, H 6.83, N
were dissolved in EtOAc. The reaction was refluxedovernightunder nitro-
gen. The crude reaction was concentrated under reduced pressure to af-
ford an orange solid. The crude product was purified by silica chroma-
calcd for C18
C
28 3 7
H N O
H27ON O
18 3 7
ꢀ
1
10.08. IR (KBr) ν (cm ): 2920.3, 2881.5, 1759.0, 1466.5, 1352.2,
tography using EtOAc/hexane 8:2 as eluent to afford the title triazoline as
1
1
281.6, 1228.3, 1199.3, 1105.7, 1062.2, 1020.5, 986.9, 851.4, 647.1.
a white solid (290 mg, 52%). H NMR (CDCl , 400 MHz, data shown
3
2
Synthesis of Heptaethylene Glycol Methyl Etherꢀ1,2,3-Δ -
for major isomer): δ = 5.22 (q, J = 6.7 Hz, 1H, ꢀCHꢀ of LA unit), 4.84
0
Triazoline-spiro[6-methyl-1,4-dioxane-2,5-dione-3,2 -bicyclo-
[
(d, J = 9.9 Hz, 1H, ꢀCHꢀ of triazoline unit), 3.65 (d, J = 9.9 Hz, 1H, ꢀ
0
2.2.1]heptane], PEG ꢀSpirolactide (4b). Azidoheptaethylen gly-
CH ꢀ of triazoline unit), 3.13 (s, 1H), 2.73 (dd, J = 14.1 Hz, J = 4.9 Hz,
7
col methyl ether, PEG
7
-N
3
, 3b (1.30 g, 3.56 mmol), and spiro[6-
1H), 2.42 (d, J = 5.2 Hz, 1H), 2.15ꢀ2.08 (m, 7H), 1.86ꢀ1.79 (m, 4H),
0
methyl-1,4-dioxane-2,5-dione-3,2 -bicyclo[2.2.1]hepta-5-ene], 2 (741 mg,
1.78ꢀ1.66 (m, 10H, CH ꢀ of LA unit and adamantane unit), 1.56
13
3
3
.56 mmol), were dissolved in EtOAc (20 mL). The reaction was
(dd, J = 14.1 Hz, J = 4.6 Hz, 1H), 1.30ꢀ1.27 (m, 1H). C NMR (CDCl
3
,
refluxed under nitrogen for 4 days. The conversion after 4 days was
100 MHz, data shown for major isomer): δ= 168.0, 167.2, 86.1, 78.2, 73.0,
1
measured by H NMR spectroscopy to be 78%. The crude reaction was
58.4, 57.4, 49.1, 43.8, 42.2, 36.4, 31.7, 29.6, 16.8. Melting point: 214ꢀ
+
concentrated under reduced pressure to give a brown oil. This solid
was purified by silica chromatography using EtOAc/hexane 7:3 as
215 °C. MS-ESI (M + H) m/z calcd for C21
H
N O
28 3 4
386.46; found
386.2. Elemental analysis: calcd forC21
H
27
N
3
O
4
: C 65.44, H 7.06, N10.9;
1
ꢀ1
eluent to afford the title triazoline as a yellow oil (1.10 g, 54%). H NMR
found: C 65.53, H 7.00, N 10.9. IR (KBr) ν (cm ): 3533.7, 3497.0,
2997.3, 2917.6, 2851.5, 2680.6, 2333.5, 1750.1, 1482.3, 1454.8, 1360.3,
1313.2, 1242.6, 1147.6, 1086.6, 1020.0, 987.4, 928.6, 855.7, 826.2, 787.1,
737.5, 693.1, 647.5, 582.3, 485.7.
(
1
CDCl
H, ꢀCHꢀ of LA unit), 4.90 (d, J = 9.8 Hz, 1H, ꢀCHꢀ of triazoline
unit), 3.82 (m, 2H), 3.75ꢀ3.61 (PEG chain, 34H), 3.53 (m, 3H), 3.35
3
, 400 MHz, data shown for major isomer): δ = 5.18 (q, J = 6.7 Hz,
6
4
dx.doi.org/10.1021/ma2016387 |Macromolecules 2012, 45, 62–69