*3.2. General Procedure for (PS-Co(BBZN)Cl2) Complex Catalyzed C*−*N Bond-Formation Reaction*

A dried Schlenk tube was charged with substrate **1 a** (320 mg, 1 mmol), **2 a** (127.6 mg, 1 mmol), BINAP (48 mg, 15 mol%), (PS-Co(BBZN)Cl2](38 mg, 12 mol%). The tube was evacuated and backfilled with N2, and Cs<sup>2</sup> CO<sup>3</sup> (975 mg, 3 mmol) followed by reagent grade 1, 4-dioxane (5 mL). The reaction mixture was heated to 100 ◦C for 10 h. After completion of reaction the mass was cooled to room temperature, filtered off the catalyst, the solvent quenched with water and diluted with ethyl acetate (10 mL). The layers were separated, and the aqueous layer was extracted with (5 mL) ethyl acetate. The combined organic layer was washed with water (10 mL), dried over anhydrous sodium sulphate and the solvent was removed in vacuum. The crude product was purified using silica gel column chromatography.

### 3.2.1. 3-(Adamantan-1-yl)-N-(4-chlorophenyl)-4-methoxyaniline (**3 a**)

Pale Yellow colored solid; mp 140–142 ◦C: <sup>1</sup>H NMR (400 MHz,CDCl3) 7.14–7.12 (d, J = 8.0 Hz, 2 H), 6.95–6.91 (m, 2 H), 6.81–6.78 (m, 3 H), 5.46 (s, 1 H), 3.80 (s, 3 H), 2.05 (m, 9 H), 1.74 (m, 6 H); <sup>13</sup>C NMR (100 MHz,CDCl3) 155.0, 144.2, 139.9, 134.8, 129.2, 123.6, 120.6, 119.1, 116.4, 112.6, 55.4, 40.6, 37.1, 29.1; LCMS (MM : ES + APCI) 368.4 (M + H)+; Anal.Calcd for C<sup>23</sup> H<sup>26</sup> ClNO: C, 75.08; H, 7.12; N, 3.81. Found: C, 75.01; H, 7.15; N, 3.88.

#### 3.2.2. 3-(Adamantan-1-yl)-4-methoxy-N-(4-methoxyphenyl)aniline (**3 b**)

Brown colored solid; mp 117–119 ◦C: <sup>1</sup>H NMR (400 MHz,CDCl3) 7.48–7.46 (d, J = 8.0 Hz, 2 H), 7.24 (m, 1 H), 6.88–6.86 (d, J = 8.0 Hz, 2 H), 6.72–6.70 (d, J = 8.0 Hz, 2 H), 5.39 (s, 1 H), 3.89 (s, 3 H), 3.83 (s, 3 H), 2.06–2.03 (m, 9 H), 1.75 (m, 6 H); <sup>13</sup>C NMR (100 MHz, CDCl3) 153.8, 142.2, 138.9, 130.4, 128.2, 122.5, 118.1, 115.5, 111.8, 55.0, 53.7, 40.3, 36.96, 28.9; LCMS (MM : ES + APCI) 364.4 (M + H)+; Anal.Calcd for C<sup>24</sup> H<sup>29</sup> NO2: C, 79.30; H, 8.04; N, 3.85. Found: C, 79.26; H, 8.11; N, 3.79.

### 3.2.3. 3-(Adamantan-1-yl)-4-methoxy-N-(4-(trifluoromethyl)phenyl)aniline (**3 c**)

Off-white colored solid; mp 124–126 ◦C: <sup>1</sup>H NMR (400 MHz,CDCl3) 7.64–7.61 (m, 2 H), 7.45–7.39 (m, 3 H), 7.24 (s, 1 H), 6.96–6.94 (d, J = 8.0 Hz, 1 H), 5.36 (s, 1 H), 3.87 (s, 3 H), 2.13–2.04 (m, 9 H), 1.77 (m, 6 H); <sup>13</sup>C NMR (100 MHz,CDCl3) 159.1, 145.1, 139.1, 131.8, 127.0, 125.7 (JCF = 25.7 Hz), 112.1, 55.2, 40.6, 37.2 (JCF = 7.6 Hz), 29.7, 29.1; LCMS (MM : ES + APCI) 402.2 (M + H)+; Anal.Calcd for C<sup>24</sup> H<sup>26</sup> F<sup>3</sup> NO: C, 71.80; H, 6.53; N, 3.49. Found: C, 71.76; H, 6.59; N, 3.41.

### 3.2.4. 3-((3-(Adamantan-1-yl)-4-methoxyphenyl)amino)phenol (**3 d**)

Off-white colored solid; mp 98–100 ◦C; <sup>1</sup>H NMR (400 MHz,CDCl3) 7.43 (s, 1 H), 7.08 (s, 1 H), 6.99–6.96 (m, 4 H), 6.84–6.82 (d, J = 8.0 Hz, 1 H), 5.62 (s, 1 H), 4.80(s, 1 H), 3.82 (s, 3 H), 2.05 (m, 9 H), 1.74 (m, 6 H); <sup>13</sup>C NMR (100 MHz,CDCl3) 159.2, 154.3, 146.2, 139.9, 129.7, 121.3, 119.9, 117.7, 115.3, 112.6, 111.2, 55.4, 40.6, 37.1, 29.1; HRMS Calcd 372.1934 Found: 372.1938 (M + H)+; Anal.Calcd for C<sup>24</sup> H<sup>29</sup> NO2: C, 79.30; H, 8.04; N, 3.85. Found: C, 79.26; H, 8.11; N, 3.79.

3.2.5. 3-(Adamantan-1-yl)-N-(2-fluorophenyl)-4-methoxyaniline (**3 e**)

Yellow colored solid; mp 106–108 ◦C: <sup>1</sup>H NMR (400 MHz, CDCl3) 7.10–7.06 (m, 1 H), 6.98–6.96 (dd, J1 = 2.7 Hz, J2 = 2.2 Hz, 2 H), 6.84–6.83 (d, J = 4.0 Hz, 1 H), 6.81 (s, 1 H), 5.50 (s, 1 H), 3.81 (s, 3 H), 2.05 (m, 9 H), 1.75 (m, 6 H); <sup>13</sup>C NMR (100 MHz,CDCl3) 158.4, 155.4, 147.1, 139.9, 134.1, 130.3, 121.5, 120.0, 118.8, 114.6, 112.8 (JCF = 53.4 Hz), 55.4, 40.5, 37.2, 29.0; LCMS (MM : ES + APCI) 352.4 (M + H)+; Anal.Calcd for C<sup>23</sup> H<sup>26</sup> FNO: C, 78.60; H, 7.46; N, 3.99. Found: C, 78.71; H, 7.39; N, 3.91.

3.2.6. 3-(Adamantan-1-yl)-4-methoxy-N-(p-tolyl)aniline (**3 f**)

Off-white colored solid; mp 108–110 ◦C: <sup>1</sup>H NMR (400 MHz,CDCl3) 7.03–7.01 (d, J = 8.0 Hz, 2 H), 6.95–6.89 (dd, J1 = 4.0 Hz, J2 = 4.0 Hz, 2 H), 6.85–6.83 (d, J = 8.0 Hz, 2 H), 6.80–6.78(d, J = 8.0 Hz, 1 H), 5.39 (s, 1 H), 3.80 (s, 3 H), 2.26 (s, 3 H), 2.05 (m, 9 H), 1.74 (m, 6 H); <sup>13</sup>C NMR (100 MHz,CDCl3) 154.2, 142.6, 139.7, 129.8, 128.9, 119.4, 117.6, 116.3, 112.7, 55.5, 40.6, 37.1, 37.0, 29.1, 20.6; LCMS (MM : ES + APCI) 348.4 (M + H)+; Anal. Calcd for C<sup>24</sup> H<sup>29</sup> NO: C, 82.95; H, 8.41; N, 4.03. Found: C, 82.90; H, 8.46; N, 3.99.

3.2.7. N-(3-Adamantan-1-yl)-4-methoxyphenyl)pyridin-3-amine (**3 g**)

Pale yellow colored solid; mp 103–104 ◦C; <sup>1</sup>H NMR (400 MHz, CDCl3) 8.42–8.41 (d, J = 4.0 Hz, 1 H), 7.47–7.43 (m, 2 H), 7.29–7.27 (m, 2 H), 7.23–7.22 (m, 2 H), 5.58 (s, 1 H), 3.85 (s, 3 H), 2.14–207 (m, 9 H), 1.79–1.73 (m, 6 H); <sup>13</sup>C NMR (100 MHz, CDCl3) 161.9, 153.0, 143.7, 136.1, 126.8, 125.9, 124.0, 123.0, 121.9, 117.6, 115.1, 56.1, 40.8, 38.0, 28.6; LCMS (MM : ES + APCI) 335.4 (M + H)+; Anal. Calcd for C<sup>22</sup> H<sup>26</sup> N<sup>2</sup> O: C, 79.00; H, 7.84; N, 8.38. Found: C, 79.08; H, 7.79; N, 8.33.

3.2.8. N-(3-Adamantan-1-yl)-4-methoxyphenyl)-5-methylpyridin-2-amine (**3 h**)

Off-white colored solid; mp 101–102 ◦C: <sup>1</sup>H NMR (400 MHz, CDCl3); 8.42 (s, 1 H), 7.53–7.47 (m, 3 H), 7.03–7.01 (d, J = 8.0 Hz, 2 H), 5.60 (s, 1 H), 3.83 (s, 3 H), 2.30 (s, 3 H), 2.09 (m, 9 H), 1.78 (m, 6 H); <sup>13</sup>C NMR (100 MHz, CDCl3) 160.2, 155.2, 145.0, 139.2, 128.9, 126.4, 121.4, 119.5, 117.4, 115.7, 54.8, 39.9, 36.4, 27.5, 27.0, 21.9; HRMS Calcd: 371.2094; Found: 371.2098 (M + H)+; Anal. Calcd for C<sup>23</sup> H<sup>28</sup> N<sup>2</sup> O: C, 79.27; H, 8.10; N, 8.04. Found: C, 79.32; H, 7.99; N, 8.09.

3.2.9. N-(3-Adamantan-1-yl)-4-methoxyphenyl)naphthalen-1-amine (**3 i**)

Pale yellow colored solid; mp 105–106 ◦C; <sup>1</sup>H NMR (400 MHz, CDCl3) 8.09–8.07 (d, J = 8.0 Hz, 1 H), 8.03–8.01 (d, J = 8.0 Hz, 1 H), 7.96–7.94 (d, J= 8 Hz, 1 H), 7.60–7.28 (m, 6 H), 5.51 (s, 1 H), 3.83 (s, 3 H), 2.13–2.05 (m, 9 H), 1.76–1.73 (m, 6 H); <sup>13</sup>C NMR (100 MHz,CDCl3) 153.9, 145.7, 138.3, 133.9, 132.7, 131.9, 128.7, 128.3, 128.2, 127.1, 126.9, 126.3, 125.9, 125.5, 111.4, 55.2, 40.4, 37.2, 29.2; LCMS (MM : ES + APCI) 384.4 (M + H)+; Anal.Calcd for C<sup>27</sup> H<sup>29</sup> NO: C, 84.55; H, 7.62; N, 3.65. Found: C, 84.61; H, 7.59; N, 3.69.

3.2.10. N-(3-Adamantan-1-yl)-4-methoxyphenyl)-1 H-inden-2-amine (**3 j**)

Pale yellow colored solid; mp 116–118 ◦C: <sup>1</sup>H NMR (400 MHz, CDCl3) 7.64–7.61 (m, 2 H), 7.45–7.39 (m, 3 H), 6.96–7.94 (d, J = 8 Hz, 2 H), 6.19 (s, 1 H), 5.34 (s, 1 H), 3.83 (s, 3 H), 3.29 (s, 2 H), 2.13–2.07 (m, 9 H), 1.77 (m, 6 H); <sup>13</sup>C NMR (100 MHz, CDCl3) 154.0, 144.4, 138.9, 132.0, 130.0, 126.0, 125.9, 120.1, 119.9, 115.5, 104.4, 55.4, 44.3, 40.8, 37.3, 29.7, 29.2; LCMS (MM : ES + APCI) 372.2 (M + H)<sup>+</sup> Anal.Calcd for C<sup>27</sup> H<sup>29</sup> NO: C, 84.06; H, 7.87; N, 3.77. Found: C, 84.11; H, 7.94; N, 3.72.

3.2.11. 4.((3-(Adamantan-1-yl)-4-methoxyphenyl)amino)phenyl)(piperidin-1-yl)methanone (**3 k**)

Off-white colored solid; mp 121–122 ◦C; <sup>1</sup>H NMR (400 MHz, CDCl3) 7.65–7.62 (m, 2 H), 7.45–7.39 (m, 3 H), 6.97–6.95 (d, J = 8.0 Hz, 1 H), 5.37 (s, 1 H), 3.87 (s, 3 H), 3.47–3.39 (m, 4 H), 2.14–2.13 (m, 9 H), 2.08–2.04 (m, 3 H), 1.78 (m, 6 H), 1.45 (m, 6 H); <sup>13</sup>C NMR (100 MHz, CDCl3) 170.4, 155.2, 145.6, 138.9, 131.8, 127.0, 125.8, 125.6, 112.5, 55.5, 46.2, 40.5, 37.2, 37.1, 29.7, 29.1, 24.4; LCMS (MM : ES + APCI) 445.2 (M + H)+; Anal.Calcd for C<sup>29</sup> H<sup>36</sup> N<sup>2</sup> O2: C 78.34; H 8.16; N 6.30; Found: C 78.39; H 8.10; N 6.24.

3.2.12. 2.(4-((3-Adamantan-1-yl)-4-methoxyphenyl)amino)-2-chloro-5-methylphenyl)-2-(4 chlorophenyl)acetonitrile (**3 l**)

Yellow colored solid; mp 129–132 ◦C; <sup>1</sup>H NMR (300 MHz, CDCl3) 7.62–7.51 (m, 3 H), 7.32–7.26 (m, 2 H), 6.84–6.81 (d, J = 12.0 Hz, 2 H), 6.35–6.25 (m, 2 H), 5.66 (s, 1 H), 5.27 (s, 1 H), 3.82 (s, 3 H), 2.16–1.66

(m, 18 H); <sup>13</sup>C NMR (75 MHz,CDCl3) 156.0, 1139.8, 136.6, 133.3, 126.8, 125.8, 125.6, 123.3, 121.7, 117.6, 55.3, 42.5, 41.6, 41.1, 40.9, 36.9, 36.5, 36.1, 35.6, 28.5, 27.9, 18.13; HRMS Calcd: 553.1784; Found: 553.1892 (M + H)+; Anal.Calcd for C<sup>32</sup> H<sup>32</sup> Cl<sup>2</sup> N<sup>2</sup> O: C 72.31; H 6.07; N 5.27; Found: C 72.39; H 6.01; N 5.24.

Off-white colored solid; mp 118–120 ◦C; 3-(adamantan-1-yl)-4-methoxy-N-(o-tolyl)aniline (**3 m**): <sup>1</sup>H NMR (400 MHz, CDCl3) 7.40 (s, 1 H), 7.36 (d, 1 H), 7.17–7.10 (m, 4 H), 6.94 (d, 1 H), 5.37 (s, 1 H), 3.87 (s, 3 H), 2.41 (s, 3 H), 2.14 (m, 6 H), 2.06 (m, 3 H), 1.77 (m, 6 H); HRMS Calcd 370.214. Found: 370.212 (M + H)+.

#### 6-Chloro-N-(p-tolyl)-9 H-fluoren-2-amine (**5 b**)

Yellow colored solid; mp 131–132 ◦C <sup>1</sup>H NMR (400 MHz, DMSO-d6); 8.10 (s, 1 H), 8.05–8.03 (d, J = 8 Hz, 1 H), 7.76 (s, 1 H), 7.53–7.51 (d, J = 8.0 Hz, 1 H), 7.38–7.21 (m, 4 H), 7.16–7.12 (m, 2 H), 5.36 (s, 1 H), 4,37 (s, 2 H), 2.39 (s, 3 H); <sup>13</sup>C NMR (100 MHz, DMSO-d6); 140.7, 140.5, 137.8, 135.5, 129.1, 127.8, 127.5, 127.0, 125.4, 123.2, 121.4, 119.9, 112.1, 110.6, 41.20, 23.5; HRMS Calcd 328.0863; Found: 328.0866 (M + Na)+; Anal.Calcd for C<sup>20</sup> H<sup>16</sup> ClN: C, 78.55; H, 5.27; N, 4.58; Found: C, 78.58; H, 5.21; N, 4.55.

#### N-(4-Methoxyphenyl)benzo[d]isoxazol-3-amine (**5 c**)

White colored solid; mp 98–100 ◦C: <sup>1</sup>H NMR (400 MHz, DMSO-d6); 8.44–8.42 (d, J = 8.0 Hz, 1 H), 8.08–8.06 (d, J = 8.0 Hz, 1 H), 8.02–8.00 (d, J = 8.0 Hz, 1 H), 7.95–7.91 (m, J = 8.0 Hz, 2 H), 7.71–7.67 (m, 1 H), 7.26–7.24 (d, J = 8.0 Hz, 2 H), 5.32 (s, 1 H), 3.88 (s, 3 H); <sup>13</sup>C NMR (100 MHz, DMSO-d6); 164.1, 159.7, 152.0, 147.4, 132.2, 127.2,125.6, 123.4, 121.7, 118.9, 114.4, 113.8, 55.2; HRMS Calcd 263.0791; Found: 263.0794 (M + Na+); Anal.Calcd for C<sup>14</sup> H<sup>12</sup> N<sup>2</sup> O2: C, 69.99; H, 5.03; N, 11.66; Found: C, 70.05; H, 5.08; N, 11.59.

### 2-(2-Chloro-4-((4-methoxyphenyl)amino)-5-methylphenyl)-2-(4-chlorophenyl)acetonitrile (**5 e**)

Off-white colored solid; mp 111–112 ◦C: <sup>1</sup>H NMR (400 MHz, DMSO-d6); 7.57–7.53 (m, 3 H), 7.51–7.42 (m, 3 H), 7.35–7.31 (m, 2 H), 7.08–7.02 (m, 2 H), 5.72 (s, 1 H), 5.32 (s, 1 H), 3.83 (s, 3 H), 2.13 (s, 3 H); <sup>13</sup>C NMR (100 MHz, DMSO-d6); 152.0, 149.8, 141.1, 140.0, 137.1, 132.4, 132.3, 132.1, 129.1, 128.6, 123.1, 120.8, 116.1, 54.99, 36.6, 17.9; HRMS Calcd 419.0688; Found: 419.0692 (M + Na+); Anal.Calcd for C<sup>22</sup> H<sup>18</sup> Cl<sup>2</sup> N<sup>2</sup> O: C, 66.51; H, 4.57; N, 7.05; Found: C, 66.59; H, 4.52; N, 7.11.

#### **4. Conclusions**

In conclusion, we prepared PS-Co (BBZN)Cl<sup>2</sup> catalyst and used it for the C−N bond formation reaction. A series of adamantyl-tethered-amino biphenylic compounds were synthesized by new protocol. Our synthetic methodology is much improved compared to existing methodologies as the catalyst is effective, inexpensive and recyclable.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2073-4344/10/11/1315/s1, SI-01: Experiment Section, SI-02: Spectral characterization Co(BBZN)Cl<sup>2</sup> , SI-03 to14: Spectral characterization of compounds 4 a-4 l.

**Author Contributions:** B.C.P., S.E.R., S.N.D. performed the organic synthesis and material characterization experiments; P.K.M., G.V., B.S.P., V.P., P.E.L. and R.K.S. supported through suggestions and guidance; K.F.-U.-R. and G.P. provided DFT calculations; B. designed the research, provided resources and wrote the manuscript. All authors have read and agreed to the published version of the manuscript.

**Funding:** B. thanks Council of Scientific and Industrial Research (No. 02(0291)17/EMR-II), Department of Biotechnology (BT/PR24978/NER/95/938/2017), Vision Group on Science and Technology, Government of Karnataka for funding. PEL thanks Tsinghua Berkeley Shenzhen Institute Faculty Start-Up Fund, the Shenzhen Development and Reform Commission Subject Construction Project for funding.

**Conflicts of Interest:** The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
