3.2.3. Synthesis of Na2[Pd(*cis*-CyHSS)]

According to Section 3.2.1, 116.77 mg (0.24 mmol) of *cis*-CyHSS and 73.9 mg (0.26 mmol) of (NH4)2[PdCl4] yielded 121 mg (0.19 mmol), 79%, yellow solid.

1H-NMR (D2O, 298 K, 360 MHz, δ): 1.39–2.21 (m, 8H, CH2–CH2), 3.59–3.69 (m, 4H, CH2–NH), 4.44–4.47 (m, 2H CH–CH), 6.89–6.91 (m, 2H, CHarom), 7.53–7.57 (m, 4H, CHarom).

1H-NMR (D2O, 268 K, 360 MHz, δ): 1.19–2.01 (m, 8H, CH2–CH2*),* 3.14 (d, *J* = 13.4, 1H, CH2–N),

3.41 (d, *J*<sup>2</sup> = 12.9 Hz, 2H, CH–CH), 3.47 (d, *J* = 13.4, 1H, CH2–N), 3.89 (d, *J* = 13.4, 1H, CH2–N), 4.24 (d, *J* = 13.4, 1H, CH2–N), 6.70 (d, *J* = 8.4 Hz, 2H, CHarom), 7.32–7.38 (m, 4H, CHarom).

13C{1H} NMR (D2O, 90 MHz), δ: 165.52, 129.41, 127.70, 123.60, 118.70, 65.11, 51.49, 24.26, 20.61. IR (ATR), ν/cm<sup>−</sup>1: 596.1, 634.3, 707.9, 1028.4, 1107.2, 1170.8, 1301.2, 1475.2, 1592.5

ESI-MS for C20H22Na2N2O8S2Pd (*m*/*z*): calcd for [M + Na]<sup>+</sup> 656.954; found 656.956.

#### 3.2.4. Synthesis of [Pd(*trans*-CyHSS)]

According to Section 3.2.1, 116.77 mg (0.24 mmol) of *trans*-CyHSS and 73.9 mg (0.26 mmol) of (NH4)2[PdCl4] yielded 132 mg (0.21 mmol), 88%, yellow solid.

1H-NMR (D2O, 298 K, 360 MHz, δ): 1.25 (s, 4H, CH2–CH2), 1.80 (s, 2H, CH2–CH2), 2.51 (s, 2H CH2–CH2), 2.79 (s, 2H, CH2–CH2), 3.74 (d, *J* = 13.3 Hz, 2H, CH2–NH), 4.17 (d, *J* = 13.3 Hz, 2H, CH–NH), 6.87–6.90 (m, 2H, CHarom), 7.52–7.55 (m, 4H, CHarom).

1H-NMR (D2O, 268 K, 360 MHz, δ): 0.75 (s, 4H, CH2–CH2), 1.30 (s, 2H, CH2–CH2), 2.04 (s, 2H CH2–CH2), 2.30 (s, 2H, CH–CH), 3.28 (d, *J* = 13.3 Hz, 2H, CH2–NH), 3.68 (d, *J* = 13.3 Hz, 2H, CH–NH), 6.38 (d, *J* = 8.3 Hz, 2H, CHarom), 7.01–7.04 (m, 4H, CHarom).

13C{1H} NMR (D2O, 90 MHz, δ): 16.54, 129.40, 128.29, 127.72, 123.53, 118.74, 67.34, 50.29, 29.44, 24.14. IR (ATR), ν/cm<sup>−</sup>1: 606.7, 708.8, 1033.3, 1105.3, 1165.3, 1298.4, 1473.3, 1590.4

ESI-MS for C20H22Na2N2O8S2Pd (*m*/*z*): calcd for [M + Na]<sup>+</sup> 656.954; found 656.956.

#### 3.2.5. Preparation of Pd–Salan Stock Solutions

In water (10 mL), 0.1 mmol of the appropriate salan and 28.4 mg (0.1 mmol) of (NH4)2[PdCl4] were dissolved. The pH was set to 7.5 with 5 M NaOH, and the solution was stirred at 60 ◦C for 10 h. With time, the light brown solution turned bright yellow. Aliquots of such stock solutions of the catalysts were added to the C–C cross-coupling reaction mixtures. 1H-NMR spectra of these stock solutions are identical to those prepared by dissolution of isolated complexes (Figures S110 and S111).
