Supporting Information
Phosphido-Diphosphine Pincer Aluminium Complexes as Catalysts for Ring Opening
Polymerization of Cyclic Esters.
Ilaria D’Auria, Marina Lamberti, Mina Mazzeo,* Stefano Milione and Claudio Pellecchia
Department of Chemistry and Biology, University of Salerno. I-84084, Via Giovanni Paolo II, 132,
Fisciano I-84084, Salerno, Italy.
Table of contents
Figure S1.1H NMR of complex 1
S2
Figure S2. 31P{1H} NMR spectrum of complex 1
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Figure S3.1H NMR of complex 2
1
S3
Figure S4. 31P{ H}NMR spectrum of complex 2
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Figure S5.1H NMR of complex 3
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Table S1. ROP of ɛ-CL by 1 at different [ɛ-CL]/ [ɛ-CL] ratios.
S5
Figure S6 Pseudo-first-order kinetic plots for ROP of ε-CLpromoted by 2.
S5
Figure S7 Pseudo-first-order kinetic plots for ROP of ε-CLpromoted by 3.
S6
Table S2. ROP of -VL by 1. Mn versus monomer conversion.
S6
Figure S8 1H NMR spectra of the CL-LA block copolymers
S7
Figure S9 DSC analyses of the CL-LA block copolymers
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S1
PPh2
P Al
CH3
CH3
PPh2
Figure S1. 1H NMR spectrum of complex 1 (400 MHz, C6D6, 298 K).
2P, d
JP-P = 144Hz
P, t
JP-P = 144Hz
Figure S2: 31P{1H}NMR spectrum of complex 1 (162.97 MHz, C6D6, 298 K).
S2
PiPr2
CH3
P
Al
CH3
PiPr2
Figure S3. 1H NMR spectrum of complex 2 (400 MHz, C6D6, 298 K).
Figure S4: 31P{1H}NMR spectrum of complex 1 (162.97 MHz, C6D6, 298 K).
S3
PHPh2
CH2CH(CH3)2
P Al
CH2CH(CH3)2
-CH-(CH3)2
PPh2
Al-CH2-
-CH-(CH3)2
Hex
Hex
Figure S5. 1H NMR spectrum of complex 3 (400 MHz, C6D6, 298 K).
S4
Table S1. Ring Opening Polymerization of ɛ-CL by 1 at different [ɛ-CL]/[Al] ratios.a
Run [ɛ-CL]/ [Al] Time
Conv
b
MnGPC
cM th
n
(min)
(%)
(˟10-3)
(˟10-3)
Mw/Mn
1
50
5
100
4.9
2.9
1.20
2
100
30
100
7.4
5.7
1.20
3
200
5
87
16.0
9.9
1.20
4
300
30
39
8.6
6.7
1.10
5
400
20
97
30.9
22.1
1.20
6
500
30
91
42.0
26.0
1.30
a
All reactions were carried out with [1]0 = 5 mM and [iPrOH]/[1] = 2, in toluene a 75°C
b
Experimental Mn and Mw/Mn values (corrected using the factor of 0.58) were determined by GPC
analysis in THF using polystyrene standards. cCalculated Mn of PCL (in gmol-1) =114,13 x ([ɛCL]/[Al + iPrOH]) x conversion ɛ-CL.
Figure S6. Pseudofirst-order kinetic plot for ROP of ε-CL promoted by 2 Pseudofirst-order rate
costant is kapp = (4.77± 0.22) × 10-3 s-1 , R= 0.995 Reaction conditions: [2] = 6 mM, [ε-CL]/ [2]/
[iPrOH]= 100/ 1/ 2; toluene-d8 as solvent; T = 50°C.
S5
Figure S7. Pseudofirst-order kinetic plot for ROP of ε-CL promoted by 3. Pseudofirst-order rate
costant is kapp = (1.22 ± 0.04) × 10-4 s-1
k = (7.32 ± 0.22) × 10-3 min-1 R= 0.996 ([3] = 6 mM,
[ε-CL] = 0.6M; [ε-CL]/[3]/[iPrOH] = 100/1/2; toluene-d8 as solvent; T = 50 °C).
Table S2. Ring Opening Polymerization of δ-VL by complex 1
Run
Time
b
Conv
c
Mn
d
Mnth
c
Mw/Mn
(˟10-3) (˟10-3)
(min)
(%)
17Nupe 25
5
40
4.0
4.2
1.20
18Nupe 25
10
70
7.3
7.4
1.22
19Nupe 25
20
98
9.8
9.3
1.25
All reactions were carried out with [Al] = 5 mM in toluene a 70°C with [δ-VL] /[Al]/ [iPrOH] = 200/1/2.
b
Experimental Mn and Mw/Mn values (corrected using the factor of 0.56) were determined by GPC analysis
in THF using polystyrene standards. cCalculated Mn of polymer (in gmol-1) =PM(monomer) x ([M]/[I0 +
iPrOH]) x conversion of monomer.
a
S6
f
a
d
LA-LA
CL-CL
b
c
e
CL-LA
LA-CL
a
A
b
c
d
e
a
B
b
c
d
e
f
f
Figure S 8: 1H NMR spectra (400 MHz, CDCl3 298 K) showing the methine signals (a, b) of
polylactide and the methylene signals (c, d, e, f) of polycaprolactone in the copolymers obtained by
1 (A) and by 2 (B).
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Figure S9. DSC thermogram of the copolymers -CL/LA obtained with complex 1 (a) and 2 (b)
(traces of the second heating cycle with a heating rate of 10°C min-1). Trace (a): Tg = +39.4 °C; Tc
= + 98.0 °C, Hc = 29.8 J/g; Tm = +132.5 °C, Hm = 29.8 J/g. The double endothermic peak
observed in the heating curve is due to a recrystallization phenomenon. Trace (b): Tg = -7.7 °C.
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