JOURNAL OF POLYMER SCIENCE: PART A: POLYMER CHEMISTRY DOI 10.1002/POLA
SCHEME 1 Synthesis of unpro-
tected glycomonomer, HEMAGl.
EXPERIMENTAL
tration. After that, the THF was removed by rota-evaporation.
The modified monomer, HEMAN, was isolated by precipita-
tion in cold methanol (yield 95%).
Materials
2-Hydroxyethyl methacrylate, HEMA (Fluka, 99%) and n-
butyl acrylate (BA; Fluka, >99%) monomers were distilled
prior to use. p-Nitrophenyl chloroformate (Fluka, 97%), D-
(þ)-Glucosamine hydrochloride (Fluka, 99%) were used
without further purification.
1
HEMAN: H NMR (300 MHz, CDCl3), d (ppm): 1.87 (s, 3H, H-
11), 4.40 (dt, 2H, 2J ¼ 3.3, 3J ¼ 6.9, H-4), 4.50 (dt, 2H, 2J ¼
3.4, 3J ¼ 7.1, H-5), 5.71 (d, 1H, 2J ¼ 1.6, H-1), 6.05 (d, 1H,
2J ¼ 1.6, H-1), 7.54 (d, 2H, 3J ¼ 9.6, H-8), 8.30 (d, 2H, 3J ¼
9.6, H-9). 13C NMR (75 MHz, CDCl3), d (ppm): 18.0 (C-11),
62.2 (C-4), 66.9 (C-5), 122.6 (C-8), 125.4 (C-9), 126.3 (C-1),
135.5 (C-2), 145.2 (C-10), 152.0 (C-6), 155.2 (C-7), 166.4
(C-3).
N,N,N0,N0,N0-pentamethyldiethylenetriamine (PMDETA; Al-
drich, 99%) was used as received. Copper (I) bromide
(CuBr; Aldrich 99.999%) and copper (I) chloride (CuCl;
Aldrich 99.99%) were used as received. Ethyl 2-bromoiso-
butyrate (EBrIB; Aldrich, 99%) was used as received. The
difunctional initiator 1,2-bis(bromoisobutyryloxy) ethane
(BrIBE) was prepared according to Karanam et al.11 Tri-
ethylamine (TEA, Scharlau), dimethyl sulfoxide (DMSO,
Scharlau), tetrahydrofurane (THF, Scharlau, 99.8%), and
N,N-dimethylformamide (DMF, Scharlau) were distilled
prior to use. Methanol (Fluka, >99.8%), diethyl ether
(SDS, 99.7%), and dichloromethane (Fluka, 99.9%) were
used as received.
Subsequently, the modified monomer with p-nitrophenyl
ꢀ
carbonate groups, HEMAN, was dissolved in DMSO at 30 C
using Pyrex double-walled reactor through which thermo-
stated water at the reaction temperature was circulated.
Equimolar concentrations of triethylamine and aminosac-
charide were added while stirring. The reaction was main-
tained for 24 h at 30 ꢀC. The glycomonomer, HEMAGl, was
isolated by precipitation using diethyl ether/dichlorome-
thane mixture (4:1) and purified by solubilization in DMF/
methanol (1:4) and posterior reprecipitation in diethyl
ether/dichloromethane mixture (4:1). The resulting glyco-
polymer was dried in vacuum at room temperature in the
presence of phosphorus pentoxide until constant weight
was reached (yield ꢁ60%).
Concanavalin A (Con A; Fluka) was used as received. Sodium
chloride (NaCl; Panreac), manganese chloride tetrahydrated,
MnCl 4H20 (99%, Fluka), calcium chloride dehydrated, CaCl
2H20 (99.5%, Fluka), potassium phosphate (KH2PO4; 99.5%,
Scharlau) were also used as received.
HEMAGl: 1H NMR (300 MHz, DMSO-d6), d (ppm): 1.88 (s,
3H, H-7), 2.99–3.16 (m, 1H, H-40), 3.20–3.31 (m, 1H, H-20),
3.38–3.71 (m, 4H, H-30, H-50, H-60), 4.12–4.22 (m, 2H, H-5),
4.22–4.29 (m, 2H, H-4), 4.33–4.71 (m, 4H, OH), 4.89 (d, 1H,
3J ¼ 5.4, H-10), 5.70 (d, 1H, 2J ¼ 1.5, H-1), 6.04 (d, 1H, 2J ¼
1.1, H-1), 6.56 (d, 0.21H, 3J ¼ 6.3, NH), 6.99 (d, 0.79H, 3J ¼
8.7, NH). 13C NMR (75 MHz, DMSO-d6), d (ppm): 18.3 (C-7),
56.7 (C-20), 61.5 (C-60), 61.9 (C-5), 63.5 (C-4), 70.5 (C-40),
71.4 (C-50), 72.4 (C-30), 91.0 (C-10), 126.5 (C-1), 136.0 (C-2),
156.3 (C-6), 166.9 (C-3).
Synthesis of Glycomonomer
The synthesis of unprotected glycomonomer based on 2-
hydroxyethyl methacrylate is illustrated in Scheme 1. The
experimental procedure essentially consists in two
plain steps: (a) activation of precursor monomers with
p-nitrophenyl chloroformate and (b) posterior saccharide
incorporation.
Briefly, HEMA (0.63 mol, 81.40 g), TEA (0.75 mol, 75.5 g),
and THF (312 mL) were placed in a Pyrex double-walled
reactor, which was entirely isolated from the outside to avoid
any contactꢀ with humidity. Once the solution was equili-
brated at 0 C, p-nitrophenyl chloroformate in THF (300 mL)
and in equimolecular ratio was successively added while stir-
ring. The reaction was performed at 0 ꢀC for 24 h. The
formed triethyl amine chlorohydrate was taken away by fil-
Polymerization Procedure
All polymerizations were performed using standard Schlenk
techniques under an argon atmosphere. Schlenk tubes were
immersed into a thermostatically controlled oil bath at the
appropriate reaction temperature. Samples were taken peri-
odically and the conversions measured by 1H NMR. Catalyst
residues were removed by passing the reaction mixtures
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