Paper
Dalton Transactions
light, silver nitrate (882.5 mg, 5.2 mmol) was added and the Then the mixture was centrifuged and the supernatant was fil-
mixture was stirred for 1 h. The white precipitation was filtered trated. The solution was slowly evaporated to dryness. The
and washed with each 5 mL of water, ethanol and diethyl obtained solid was washed with acetone and dried under
ether. Finally, the product was dried under vacuum. Yield: vacuum to obtain 2b with a yield of 147.98 mg (31.4%). IR
762.6 mg (82.0%). IR (ATR, cm−1) 2935 (w), 1542 (m), 1499 (s, (ATR, cm−1) 3409 (w), 2936 (w), 1620 (s, ˜νasym(OCO−)), 1348 (s,
˜νasym(OCO−)), 1396 (m), 1346 (m, ˜νsym(OCO−)). Elemental ana- ˜νsym(OCO−)). MS (ESI-MS, neg. ion detection mode, m/z) 474
lysis: calculated: C: 20.14%, H: 1.69%, observed: C: 19.80%, H: [M + Na − H]−, 451 [M − H]− 338 [M − DACH − H]−.1H NMR
1.69%
(400 MHz, DMSO-d6, δ): 5.86 (d, 2H, –NH2), 5.14 (t, 2H, –NH2),
2.68 (dq, 4H, –CH2), 2.27 (t, 1H, –CH) 2.05 (t, 1H, –CH) 1.81 (d,
2H, –CH2) 1.65 (qi, 2H, –CH2) 2.44 (d, 2H, –CH2) 1.21 (d, 2H,
Synthesis of cis-[Pt(I2)(NH3)2] (1a)
Potassium tetrachloroplatinate(II) (500 mg, 1.2 mmol) was dis- –CH2) 1.03 (m, 2H, –CH2). 13C NMR (62.86 MHz, DMSO-d6, δ):
solved in 15 mL of water and then potassium iodide (1595 mg, 177.3 (2Cq, CvO), 62.0 (2Ct), 55.5 (1Cq), 31.5 (2Cs), 30.2 (2Cs),
9.6 mmol) was added. The mixture was stirred for 30 min to 24.0 (2Cs), 15.0 (1Cs). 195Pt NMR (53.75 MHz, DMSO-d6, δ
obtain a brown solution with the intermediate product potass- ppm): −1906.
ium tetraiodoplatinate(II). Then 33% ammonia solution
(1.54 mL, 26.6 mmol) was added. After 2 hours yellow solid
Synthesis of cis,trans,cis-[Pt(CBDC)(succ)(Br)(NH3)2] (3a)
precipitated. This solid was washed with 5 mL of water, 2a (50 mg, 0.13 mmol) was suspended in 5 mL of water and
ethanol and diethyl ether and afterwards dried under vacuum 10 mL of acetone and then succinic anhydride (26.96 mg,
to obtain 1a. Yield: 498.9 mg (85.8%). IR (ATR, cm−1) 3267(m, 0.27
mmol)
was
added.
After
dissolving
the
˜νsym(NH3)), 3194 (m), 1288 (s), 1259 (s) 736 (s).
N-bromosuccinimide (23.98 mg, 0.13 mmol) was added and
the mixture was stirred for 5 h under the exclusion of light.
The solution was evaporated, a yellow oil was washed with
Synthesis of cis-[Pt(Cl2)(DACH)] (1b)
Potassium tetrachloroplatinate(II) (500 mg, 1.2 mmol) was dis- acetone and evaporated to dryness. This procedure was
solved in 15 mL of water and solid 1,2-diaminocyclohexane repeated until a yellowish solid was obtained. The final
(137.5 mg, 1.2 mmol) was added. The mixture was stirred for product was dried under vacuum to obtain 3a with a yield of
24 h, and the resulting yellow precipitate was filtered and 53.34 mg (69.8%). IR (ATR, cm−1) 3203 (w, ˜νsym(NH3)), 1702 (w)
washed with each 5 mL of water, ethanol and diethyl ether to 1620(s, ˜νasym(OCO−)), 1422 (w) 1339(s, ˜νsym(OCO−)). MS
obtain 1b. Yield: 411.5 mg (89.3%). IR (ATR, cm−1) 3272 (m), (ESI-MS, negative ion detectionmode, m/z) 590 [M + Na − H]−,
3182 (m), 2934 (m), 2863 (w) 1563 (s, ˜νasym(OCO−)).1H NMR 567 [M − H]−. 13C NMR (DMSO-d6, 125.7 MHz): δ 14.8 (OCO–
(400 MHz, DMSO-d6, δ): 6.40–4.90 (m, 4H, –NH2), 2.35 (s, 1H, C–CH2–CH2), 28.6 (OCO–CH2–CH2–COOH), 29.3 (OCO–C–
–CH), 2.09 (s, 1H, –CH), 1.90 (m, 2H, –CH2) 1.46 (dd, 2H, CH2–CH2), 30.1(OCO–C–CH2–CH2), 30.8 (OCO–CH2–CH2–
–CH2) 1.26 (m, 2H, –CH2) 0.99 (dt, 2H, –CH2). 13C NMR COOH), 53.9(OCO–C–CH2–CH2), 172.5 (OCO–CH2–CH2–
(62.86 MHz, DMSO-d6, δ): 61.5 (1Ct), 61.3 (1Ct), 31.6 (1Cs), 31.4 COOH), 174.6 (OCO–C–CH2–CH2), 175.3 (OCO–C–CH2–CH2),
(1Cs), 23.9 (1Cs), 23.7 (1Cs).
178.2 (OCO–CH2–CH2–COOH) ppm.195Pt NMR (53.75 MHz,
DMSO-d6, δ ppm): 1090.
Synthesis of [Pt(CBDC)(NH3)2] (2a)
Synthesis of cis,trans,cis-[Pt(CBDC)(succ)(Br)(DACH)] (3b)
1a (498.9 mg, 1.0 mmol) was suspended in 10 mL of water and
10 mL of ethanol. Disilvercyclobutane–carboxylate (368.6 mg, 2b (50 mg, 0.11 mmol) was suspended in 5 mL of water and
1.0 mmol) was added and the mixture was stirred for 48 h in 10 mL of acetone and succinic anhydride (22.17 mg,
the dark. Then the mixture was centrifuged and the super- 0.22 mmol) was added. After dissolving all starting materials,
natant was filtrated. The solvents were removed by slow evapor- the N-bromosuccinimide (19.72 mg, 0.11 mmol) was added
ation. The obtained solid was washed with acetone and dried and the mixture was stirred for 5 h under the exclusion of
under vacuum to obtain 2a with a yield of 183.7 mg (48.0%). light. The solution was evaporated, a yellow oil was washed
IR (ATR, cm−1) 3262(m, ˜νsym(NH3)), 2925 (w), 1638 (s), 1694 (s, with acetone and evaporated again. This procedure was
˜νasym.(OCO−)), 1376 (s, ˜νsym(OCO−)). 1346 (s). MS (ESI-MS, repeated until a yellowish solid was obtained. This product
negative ion detection mode, m/z): 370 [M − H]−, 265 [M − was dried under vacuum to obtain 3b with a yield of 31.11 mg
(CBDC) + (H2O)2]−. 1H NMR (400 MHz, DMSO-d6, δ): 4.09 (s, (43.4%). IR (ATR, cm−1) 3143 (w), 2944 (w), 1709 (w) 1629 (s,
6H, –NH3), 2.67 (t, 4H, –CH2), 1.64 (qi, 2H, –CH2). 13C NMR ˜νasym(OCO−)), 1447 (w) 1342 (s, ˜νsym(OCO−)). MS (ESI-MS, nega-
(62.86 MHz, DMSO-d6, δ): 177.6 (2Cq, CvO), 55.6 (1Cq), 30.4 tive mode, m/z) 647 [M − H]−, 360 [M − (succ) − (CBDC) − Br +
(2Cs), 15.0 (1Cs). 195Pt NMR (53.75 MHz, DMSO-d6, δ ppm): (OH)3]−. 13C NMR (DMSO-d6, 125.7 MHz): δ 15.5 (OCO–C–
−1705.
CH2–CH2), 23.4 (NH2–CH–CH2–CH2), 23.5 (NH2–CH–CH2–
CH2),29.6 (OCO–CH2–CH2–COOH), 30.6 (NH2–CH–CH2–CH2),
30.7 (OCO–C–CH2–CH2), 30.9 (NH2–CH–CH2–CH2), 31.6
Synthesis of [Pt(CBDC)(DACH)] (2b)
1b (396.52 mg, 1.0 mmol) was dissolved in 10 mL of water and (OCO–C–CH2–CH2), 31.8 (OCO–CH2–CH2–COOH), 55.7(OCO–
10 mL of ethanolicdisilvercyclobutane–carboxylate (372.16 mg, C–CH2–CH2), 61.3 (NH2–CH–CH2–CH2), 61.4 (NH2–CH–CH2–
1.0 mmol) was added and the mixture was stirred for 48 h. CH2), 173.7 (OCO–CH2–CH2–COOH), 176.2 (OCO–C–CH2–
15474 | Dalton Trans., 2018, 47, 15465–15476
This journal is © The Royal Society of Chemistry 2018