30
G.G. Briand et al. / Journal of Organometallic Chemistry 806 (2016) 22e32
SigmaeAldrich. Trimethylindium was used as received from Strem.
H2(SNNS), H2(SNNSPr) [34], H2(ONS2), H2(NNS2Pr) [35], H2(NNS2)
[36], were prepared according to literature methods. H(pyrS) was
prepared from the reaction of the corresponding amine with
ethylene sulfide in toluene at 100 ꢀC for 18 h. The solvent was
removed and the residual liquid fractionally distilled under reduced
crystals (0.786 g, 2.43 mmol 78%). Anal. Calc. for C8H18InNOS2: C,
29.73; H, 5.61; N, 4.33; S, 19.84. Found: C, 29.74; H, 5.72; N, 4.26; S,
19.89. Mp ¼ 132e136 ꢀC. FT-IR (cmꢁ1): 591w, 669vs, 691 s, 820w,
883w, 934 m, 971 m, 998 s, 1025 m, 1077 s, 1098 m, 1112 s, 1211w,
1229 m, 1282 m, 1332w, 1351w, 1448 m, 2831w, 2880w, 2916w. FT-
Raman (cmꢁ1): 126 s, 157s, 270 m, 314vs, 365w, 497vs [v(IneCMe)],
670 m, 1147 m, 1441w, 2991 m, 2952 m. NMR data (CDCl3, ppm), 1H
NMR: 0.00 (s, 3H, MeIn), 2.50e2.62 (m, 4H, SCH2), 2.69 (t,
3JHH ¼ 5 Hz, 2H, NCH2CH2O), 2.75e2.96 (m, 4H, SCH2CH2N), 3.12 (s,
pressure to give the desired product. D,L-lactide and L-lactide were
purchased from Purac and were purified 3 ꢂ vacuum sublimations
prior to polymerisation. ε-Caprolactone and benzyl alcohol were
obtained from SigmaeAldrich, dried over calcium hydride and
distilled under inert atmosphere prior to use. Toluene, tetrahy-
drofuran (thf) and hexanes were dried using an MBraun SPS col-
umn solvent purification system. Diethyl ether, anhydrous
99% þ was used as received from SigmaeAldrich. All reactions were
performed under an atmosphere of inert dinitrogen using standard
Schlenk techniques unless otherwise indicated.
3
3H, OMe), 3.36 (t, JHH ¼ 5 Hz, 2H, NCH2CH2O),13C{1H} NMR: ꢁ1.5
(MeIn), 24.6 (SCH2), 52.2 (NCH2CH2O), 55.3 (SCH2CH2N), 59.0
(OMe), 67.6 (NCH2CH2O).
4.5. Preparation of [MeIn(NNS2)] (6)
H2(NNS2) (0.739 g, 3.12 mmol) in toluene (3 mL) was added
drop-wise to a stirring solution of InMe3 (0.500 g, 3.12 mmol) in
toluene (3 mL). The solution was stirred for 3 h at 23 ꢀC yielding a
clear colorless solution. The reaction mixture was concentrated to
3 mL under vacuum and allowed to sit at ꢁ15 ꢀC. After 6 d, the
mixture was filtered to remove 6 as colorless crystals (0.782 g,
2.15 mmol 69%). Anal. Calc. for C11H25InN2S2: C, 36.27; H, 6.92; N,
7.69; S, 17.60. Found: C, 36.49; H, 7.11; N, 7.56; S, 17.59.
Mp ¼ 108e111 ꢀC. FT-IR (cmꢁ1): 557w, 655vs, 666vs, 741 s, 788w,
885w, 935w, 953w, 997 m, 1010 s, 1058 s, 1078 s, 1093 m, 1128w,
1185w, 1271w, 1303 m, 1331w, 1389w, 1442 m, 1472 m, 2834 m,
2859w, 2913w, 2975w. FT-Raman (cmꢁ1): 139 m, 171 s, 264 m,
294 m, 328 m, 375w, 426w, 477vs [v(IneCMe)], 509vw, 676w,
1134 m, 1447w, 2929 m, 2953 m. NMR data (CDCl3, ppm), 1H NMR:
0.00 (s, 3H, MeIn), 1.41 (t, 3JHH ¼ 7 Hz, 6H, NCH2CH3), 2.77e3.03 [m,
4.2. Preparation of [MeIn(SOOS)2]2 (3)
H2(SOOS) (0.300 g, 1.65 mmol) in toluene (2 mL) was added
drop-wise to a stirring solution of InMe3 (0.263 g, 1.65 mmol) in
toluene (5 mL). The solution was stirred for18 h at RT, yielding a
cloudy solution and a white precipitate. The reaction mixture was
filtered to remove 3 as a white powder (0.300 g, 0.967 mmol 59%).
After sitting overnight at 23 ꢀC, the reaction solution was filtered to
afford block-like crystals of 3 (0.108 g, 0.348 mmol, 21%). Anal. Calc.
for C14H30In2O4S4: C, 27.11; H, 4.87; N, 0.00. Found: C, 27.16; H, 5.05;
N, <0.3. Mp 157e158 ꢀC. FT-IR (cm-1): 658 m, 674 m, 712 s, 809 w,
900 m, 1012 m, 1084 s, 1123 m, 1283 m, 1369 w, 1418 w, 1464 w,
2360 w, 2869 w, 2902 w, 2981 w. FT-Raman (cmꢁ1): 131 s, 181 m,
277 m, 329vs, 506 s [
y
(IneCMe)], 660w, 675w, 1140 s, 2871w,
12H, (SCH2CH2)2NCH2CH2N], 3.13 (q, 3JHH ¼ 7 Hz, 4H, NCH2CH3). 13
C
2903w, 2927 m. NMR data (CDCl3, ppm), 1H NMR: 0.00 (s, 3H,
{1H} NMR: ꢁ0.8 (MeIn), 9.3 (NCH2CH3), 23.0 (SCH2), 47.5, 47.7, 47.8
[NCH2CH2N(CH2CH3)2], 57.4 (SCH2CH2).
3
MeIn), 2.63 (t, JHH ¼ 5 Hz, 4H, SCH2), 3.38e3.44 (m, 8H,
CH2OCH2CH2OCH2). 13C{1H} NMR: ꢁ0.6 (MeIn), 27.7 (SCH2), 68.2
(OCH2CH2O), 72.2 (SCH2CH2O).
4.6. Preparation of [MeIn(NNS2Pr)]2 (7)
4.3. Preparation of [MeIn(SNNS)] (4)
H2(SNNSPr) (0.329 g, 1.32 mmol) in toluene (3 mL) was added
drop-wise to a stirring solution of InMe3 (0.200 g, 1.25 mmol) in
toluene (3 mL). The solution was stirred for 3 h at 23 ꢀC yielding a
clear colorless solution. The solvent was removed under vacuum
and the resulting product was extracted with hexanes (2 ꢂ 3 mL).
The mixture was filtered and the filtrate was stored at 23 ꢀC. After
6 d, the mixture was filtered to give 7 as colorless crystals (0.098 g,
0.26 mmol 21%). Anal. Calc. for C12H27InN2S2: C, 38.10; H, 7.19; N,
7.41. Found: C, 37.91; H, 7.50; N, 7.37. Mp ¼ 86e88 ꢀC (d). FT-IR
(cmꢁ1): 611 m, 668vs, 782w, 912w, 973w, 1001 m, 1022 m,
1067 s, 1086 s, 1132w, 1159w, 1196 m, 1265w, 1299 m, 1331w,
1370 m, 1448 m, 1460 m, 2797w, 2924w 2964 m. FT-Raman (cmꢁ1):
122 s, 145 s, 192 m, 260 s, 309 s, 498vs [v(IneCMe)], 672 m, 1056w,
1147 m, 1453w, 2855 m, 2925 s. NMR data (CDCl3, ppm), 1H NMR:
0.00 (s, 3H, MeIn), 0.81 (t, 3JHH ¼ 7 Hz, 6H, NCH2CH3), 1.31e1.46 (m,
H2(SNNS) (0.652 g, 3.12 mmol) in thf (6 mL) was added drop-
wise to a stirring solution of InMe3 (0.500 g, 3.12 mmol) in thf
(6 mL). The solution was stirred for 3 h at 23 ꢀC, yielding a cloudy
solution and a white precipitate. The reaction mixture was filtered
to remove 4 as a colorless powder (0.824 g, 2.45 mmol 79%). The
filtrate was stored at at ꢁ15 ꢀC for 1 d and filtered to give 4 as
colorless crystals (0.040 g, 0.12 mmol, 4%) Anal. Calc. for
C9H21InN2S2: C, 32.15; H, 6.30; N, 8.33; S, 19.07. Found: C, 32.23; H,
6.43; N, 8.27; S, 19.09. Mp ¼ 215e219 ꢀC. FT-IR (cmꢁ1): 669vs,
696vs, 744w, 766 m, 884 m, 941 s, 1001w, 1021 m, 1034 m, 1077 m,
1213w, 1279w, 1300 m, 1314w, 1460 s, 2826w, 2857w, 2916w,
2956w. FT-Raman (cmꢁ1): 130 s, 158 s, 199 m, 269 m, 298 s, 335 s,
369w, 480 s [
1156 m [ (SNNS)],1438w,1454w, 2858w, 2921 m. NMR data (CDCl3,
ppm), 1H NMR: 0.00 (s, 3H, MeIn), 2.29 (s, 6H, NMe), 2.66e2.83 (m,
12H, MeIn(SCH2CH2NMeCH2CH2NMeCH2CH2S)];
13C{1H}
n(IneCMe)], 505 s [nasym(IneCMe)2], 670 m [n(SeC)],
3
d
2H, NCH2CH2CH2N, 2.16 [t, JHH ¼ 7 Hz, 2H, CH2N(CH2CH3)2], 2.29
(q, 3JHH ¼ 7 Hz, 4H, NCH2CH3), 2.39e2.60 [m, 6H, (SCH2CH2)2NCH2],
2.76e2.93 [m, 4H, SCH2. 13C{1H} NMR: ꢁ1.6 (MeIn), 11.9 (NCH2CH3),
20.2 (NCH2CH2CH2N), 24.5 (SCH2), 47.1 (NCH2CH3), 50.8
[CH2N(CH2CH3)2], 51.4 [(SCH2CH2)2NCH2], 54.6 (SCH2CH2N).
NMR: ꢁ5.3 (MeIn), 24.2 (SCH2), 41.9 (NMe), 54.7 (NCH2CH2N), 62.0
(SCH2CH2N).
4.4. Preparation of [MeIn(ONS2)]3 (5)
4.7. Preparation of [MeIn(pyrS)2] (8)
H2(ONS2) (0.611 g, 3.12 mmol) in toluene (3 mL) was added
drop-wise to a stirring solution of InMe3 (0.500 g, 3.12 mmol) in
toluene (3 mL). The solution was stirred for 3 h at 23 ꢀC, yielding a
clear colorless solution. The reaction mixture was concentrated to
1 mL under vacuum, layered with hexanes (3 mL) and allowed to sit
at 23 ꢀC. After 7 d, the mixture was filtered to remove 5 as colorless
H(pyrS) (0.328 g, 2.50 mmol) in diethyl ether (3 mL) was added
drop-wise to a stirring solution of InMe3 (0.200 g, 1.25 mmol) in
diethyl ether (3 mL). The solution was stirred for 3 h at 23 ꢀC,
yielding a cloudy solution. The reaction mixture was filtered to
remove 8 as a colorless powder (0.255 g, 0.653 mmol, 52%). The
reaction filtrate was allowed to sit at 23 ꢀC. After 6 d, the mixture