Supporting Information Molecular Iodine-Catalyzed Aerobic α,β-diamination of Cyclohexanones with 2- Aminopyrimidine and 2-Aminopyridines Thanh Binh guyen,* Ludmila Ermolenko, Pascal Retailleau, and Ali Al-Mourabit* General information Reagents were obtained from commercial supplier and used without further purification. Analytical thin layer chromatography (TLC) was purchased from Merck KGaA (silica gel 60 F254). Visualization of the chromatogram was performed by UV light (254 nm) or phosphomolybdic acid or vanilline stains. Flash column chromatography was carried out using kieselgel 35-70 µm particle sized silica gel (230-400 mesh). MR Chemical shifts are reported in (δ) ppm relative to tetramethylsilane (TMS) with the residual solvent as internal reference (CDCl 3, δ 7.26 ppm for 1 H and δ 77.0 ppm for 13 C; DMS-d 6, δ 2.50 ppm for 1 H and δ 39.5 ppm for 13 C; CD 3 D, δ 3.31 ppm for 1 H and δ 49.0 ppm for 13 C). Data are reported as follows: chemical shift, multiplicity (s = singlet, d = doublet, t = triplet, q = quartet, m = multiplet), coupling constants (Hz) and integration. General procedure A mixture of 2-cyclohexanone 1 (2.5 mmol), 2-aminopyrimidine or 2-aminopyridine 2 (1.25 mmol), and molecular iodine (32 mg, 0.125 mmol) in acetic acid or isobutyric acid (2 ml) was stirred under an atmosphere of oxygen (balloon) in a 17-mL test tube at indicated temperatures (Table 1, Schemes 2 and 3) for 24 h. After being cooled to room temperature, the volatiles were removed in vacuo (0.1 mbar, 100 C). The crude reaction mixture after treatment with a slight excess of H 3 in CH 3 H was concentrated again and purified by silica gel column chromatography (EtAc or CH 2 Cl 2 /CH 3 H) to afford the desired adduct 3. S1
8,9-Dihydrobenzo[4,5]imidazo[1,2-a]pyrimidin-6(7H)-one (3aa) Purification of the crude mixture by silica gel column chromatography (AcEt) afforded the product as a brown solid (163 mg, 70%). 1 H MR spectroscopic data matched literature report. 1 9-Methyl-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyrimidin-6(7H)-one (3ba) Me Purification of the crude mixture by silica gel column chromatography (AcEt) afforded the product as a brown solid (188 mg, 75%). 1 H MR (300 MHz, CDCl 3 ) δ 9.50 (dd, J = 6.8, 1.6 Hz, 1H), 8.75 (m, 1H), 7.13 (dd, J = 6.8, 4.2 Hz, 1H), 3.23 (dd, J = 17.2, 4.3 Hz, 1H), 2.78 (m, 2H), 2.56 (m, 1H), 2.44 (m, 1H), 1.25 (d, J = 6.2 Hz, 3H). 13 C MR (75 MHz, CDCl 3 ) δ 188.5, 161.8, 159.7, 153.3, 147.8, 135.4, 110.5, 46.4, 33.5, 31.6, 21.2. HRMS-ESI+: m/z [M + H]+ calcd for C 11 H 12 3 : 202.0980; found: 202.0998. 9-(tert-Butyl)-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyrimidin-6(7H)-one (3ca) Purification of the crude mixture by silica gel column chromatography (AcEt) afforded the product as a brown oil (158 mg, 52%). 1 H MR (300 MHz, CDCl 3 ) δ 9.45 (dd, J = 6.5, 1.7 Hz, 1H), 8.76 (dd, J = 4.4, 1.7 Hz, 1H), 7.13 (dd, J = 6.5, 4.4 Hz, 1H), 3.27 (dd, J = 16.7, 4.3 Hz, 1H), 2.83 (m, 2H), 2.52 (dd, J = 16.7, 13.3 Hz, 1H), 2.20 (m, 1H), 1.05 (s, 9H). 13 C MR (75 MHz, CDCl 3 ) δ 189.0, 162.2, 153.6, 150.8, 135.7, 117.5, 110.8, 47.0, 40.3, 32.7, 27.4 (3 carbons), 27.2. HRMS-ESI+: m/z [M + H]+ calcd for C 14 H 18 3 : 244.1450; found: 244.1454. 1 guyen, T. B. Corbin, M. Retailleau, P. Ermolenko, L. Al-Mourabit, A. rg. Lett. 2015, 17, 4956. S2
8,9-Dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ab) Purification of the crude mixture by silica gel column chromatography (MeH:AcEt 1:9) afforded the product as a brown powder (165 mg, 71%). 1 H MR (300 MHz, CD 3 D) δ 8.29 (d, J = 7.2 Hz, 1H), 7.58 (d, J = 8.8 Hz, 1H), 7.44 (m, 1H), 7.03 (t, J = 7.0 Hz, 1H), 3.17 (t, J = 6.1 Hz, 2H), 2.72 (t, J = 6.6 Hz, 2H), 2.38 (dd, J = 6.6, 6.1 Hz, 2H). 13 C MR (75 MHz, CD 3 D) δ 195.0, 145.4, 136.5, 136.1, 127.8, 125.2, 117.6, 113.8, 38.3, 23.0, 19.6. HRMS-ESI+: m/z [M + H]+ calcd for C 11 H 11 2 : 187.0871; found: 187.0862. 3-Fluoro-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ac) F Purification of the crude mixture by silica gel column chromatography (AcEt) afforded the product as a brown solid (153 mg, 60%). 1 H MR (300 MHz, CDCl 3 ) δ 7.86 (m, 1H), 7.56 (dd, J = 9.8, 4.9 Hz, 1H), 7.16 (t, J = 9.8 Hz, 1H), 3.05 (m, 2H), 2.68 (m, 2H), 2.34 (m, 2H). 13 C MR (75 MHz, CDCl 3 ) δ 193.4, 153.8 (d, J = 238.0 Hz), 143.3, 139.3, 135.3, 120.1 (d, J = 9.7 Hz), 119.2 (d, J = 26.6 Hz), 110.6 (d, J = 38 Hz), 38.9, 23.2, 20.5. HRMS-ESI+: m/z [M + H]+ calcd for C 11 H 10 F 2 : 205.0777; found: 205.0781. 2-Chloro-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ad) Cl Purification of the crude mixture by silica gel column chromatography (AcEt) afforded the product as a brown powder (157 mg, 57%). 1 H MR (300 MHz, CDCl 3 ) δ 7.98 (s, 1H), 7.61 (d, J = 8.8 Hz, 1H), 7.22 (d, J = 8.8 Hz, 1H), 3.07 (t, J = 6.3 Hz, 2H), 2.73 (t, J = 6.4 Hz, 2H), 2.38 (m, 2H). 13 C MR (75 MHz, CDCl 3 ) δ 193.3, 143.9, 138.9, 134.2, 128.0, 122.1, 121.8, 119.9, 38.9, 23.3, 20.2. HRMS-ESI+: m/z [M + H]+ calcd for C 11 H 10 Cl 2 : 221.0482; found: 221.0461. S3
2-Bromo-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ae) Br Purification of the crude mixture by silica gel column chromatography (AcEt) afforded the product as a brown powder (149 mg, 45%). 1 H MR (300 MHz, CDCl 3 ) δ 8.11 (s, 1H), 7.60 (d, J = 9.4 Hz, 1H), 7.31 (d, J = 9.4 Hz, 1H), 3.08 (t, J = 5.7 Hz, 2H), 2.76 (t, J = 5.9 Hz, 2H), 2.40 (m, 2H). 13 C MR (75 MHz, DMS-d6) δ 193.5, 143.4, 138.6, 136.5, 130.4, 126.4, 119.7, 107.6, 39.2, 23.2, 20.4. HRMS-ESI+: m/z [M + H]+ calcd for C 11 H 10 Br 2 : 264.9977; found: 264.9962. 3-Bromo-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3af) Br Purification of the crude mixture by silica gel column chromatography (MeH:AcEt 1:9) afforded the product as a brown powder (222 mg, 67%). 1 H MR (300 MHz, CD 3 D) δ 8.25 (dd, J = 7.2, 0.6 Hz, 1H), 7.82 (dd, J = 2.0, 0.6 Hz, 1H), 7.18 (dd, J = 7.2, 2.0 Hz, 1H), 3.16 (t, J = 6.1 Hz, 2H), 2.70 (t, J = 6.6 Hz, 2H), 2.38 (m, 2H). 13 C MR (75 MHz, CD 3 D) δ 195.3, 138.4, 137.8, 127.3, 122.9, 120.9, 118.9, 39.5, 24.2, 21.1. HRMS-ESI+: m/z [M + H]+ calcd for C 11 H 10 Br 2 : 264.9977; found: 264.9981. 4-Bromo-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ag) Br Purification of the crude mixture by silica gel column chromatography (AcEt) afforded the product as a brown solid (172 mg, 65%). 1 H MR (300 MHz, CDCl 3 ) δ 7.86 (dd, J = 6.8, 1.0 Hz, 1H), 7.47 (dd, J = 6.8, 1.0 Hz, 1H), 6.72 (t, J = 6.8 Hz, 1H), 3.01 (t, J = 6.2 Hz, 1H), 2.65 (m, 2H), 2.30 (quint, J = 6.2 Hz, 2H). 13 C MR (75 MHz, CDCl 3 ) δ 193.1, 143.7, 138.5, 135.7, 128.8, 123.3, 113.8, 113.6, 38.7, 23.0, 20.6. HRMS-ESI+: m/z [M + H]+ calcd for C 11 H 10 Br 2 : 264.9977; found: 264.9971. S4
6-oxo-6,7,8,9-tetrahydrobenzo[4,5]imidazo[1,2-a]pyridine-3-carbonitrile (3ah) C Purification of the crude mixture by silica gel column chromatography (AcEt) afforded the product as a brown powder (140 mg, 53%). 1 H MR (300 MHz, DMS-d6) δ 9.33 (s, 1H), 7.77 (d, J = 9.0 Hz, 1H), 7.59 (dd, J = 9.0, 1.5 Hz, 1H), 3.14 (t, J = 6.2 Hz, 2H), 2.61 (t, J = 6.2 Hz, 2H), 2.24 (m, 2H). 13 C MR (75 MHz, DMS-d6) δ 195.3, 138.4, 137.8, 127.3, 122.9, 120.9, 118.9, 39.5, 24.2, 21.1. HRMS-ESI+: m/z [M + H]+ calcd for C 12 H 10 3 : 221.0482; found: 221.0461. 3-(Trifluoromethyl)-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ai) CF 3 Purification of the crude mixture by silica gel column chromatography (AcEt) afforded the product as a brown powder (168 mg, 53%). 1 H MR (300 MHz, CDCl 3 ) δ 8.11 (d, J = 7.5 Hz, 1H), 7.96 (s, 1H), 7.10 (d, J = 7.5 Hz, 1H), 3.15 (t, J = 5.5 Hz, 2H), 2.77 (t, J = 5.9 Hz, 2H), 2.42 (m, 2H). 13 C MR (75 MHz, CDCl 3 ) δ 193.3, 143.6, 134.9, 128.3 (q, J = 35.0 Hz), 125.1, 122.8 (q, J = 274.0 Hz), 117.6 (q, J = 5.2 Hz), 109.4 (q, J = 2.8 Hz), 38.7, 23.0, 20.3. HRMS-ESI+: m/z [M + H]+ calcd for C 12 H 10 F 3 2 : 255.0745; found: 255.0739. 2-(Trifluoromethyl)-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3aj) CF 3 Purification of the crude mixture by silica gel column chromatography (Hept:AcEt / 1:9) afforded the product as a brown powder (200 mg, 63%). 1 H MR (300 MHz, CDCl 3 ) δ 8.25 (dd, J = 1.9, 0.8 Hz, 1H), 7.64 (2t, J = 9.7, 0.8 Hz, 1H), 7.29 (dd, J = 9.7, 1.9 Hz, 1H), 3.08 (t, J = 6.3 Hz, 2H), 2.66 (dd, J = 7.2, 5.9 Hz, 2H), 2.33 (m, 2H). 13 C MR (75 MHz, CDCl 3 ) δ 193.2, 145.1, 139.6, 135.4, 123.4 (q, J = 5.7 Hz), 123.1 (q, J = 272.0 Hz), 122.1 (q, J = 2.8 Hz), 120.2, 118.0 (q, J = 35.0 Hz), 38.7, 23.1, 20.3. S5
HRMS-ESI+: m/z [M + H]+ calcd for C 12 H 10 F 3 2 : 255.0745; found: 255.0758. 7,8,9,10-Tetrahydro-6H-cyclohepta[4,5]imidazo[1,2-a]pyridin-6-one (3eb) Purification of the crude mixture by silica gel column chromatography (MeH:AcEt/1:9) afforded the product as a brown powder (20 mg, 8%). 1 H MR (300 MHz, CD 3 D) δ 8.23 (dt, J = 7.2, 0.8 Hz, 1H), 7.56 (dt, J = 9.2, 0.8 Hz, 1H), 7.40 (m 1H), 7.02 (td, J = 6.8, 0.8 Hz, 1H), 3.18 (t, J = 6.2 Hz, 2H), 2.87 (t, J = 6.2 Hz, 2H), 2.22 (m, 2H), 2.03 (m, 2H). 13 C MR (75 MHz, CDCl 3 ) δ 198.6, 146.0, 142.7, 132.0, 128.6, 126.4, 118.8, 115.0, 45.0, 26.5, 26.1, 23.6. HRMS-ESI+: m/z [M + H]+ calcd for C 12 H 13 2 : 201.1028; found : 201.1032 8,9,10,11-Tetrahydrocycloocta[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3fb) Purification of the crude mixture by silica gel column chromatography (MeH:AcEt/1:9) afforded the product as a brown powder (27 mg, 10%). 1 H MR (300 MHz, CD 3 D) δ 8.42 (d, J = 7.2, Hz, 1H), 7.56 (d, J = 9.2, Hz, 1H), 7.37 (m 1H), 7.01 (t, J = 7.2, Hz, 1H), 3.50 (t, J = 7.0 Hz, 2H), 3.02 (t, J = 7.0 Hz, 2H), 1.88 (m, 4H), 1.48 (m, 2H). 13 C MR (75 MHz, CDCl 3 ) δ 198.7, 145.9, 142.5, 130.6, 128.2, 126.1, 119.0, 115.1, 42.2, 24.8 (two carbons), 24.6, 23.2. HRMS-ESI+: m/z [M + H]+ calcd for C 13 H 15 2 : 215.1184; found : 215.1192 8,9,10,11-Tetrahydrocyclododeca[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3gb) Purification of the crude mixture by silica gel column chromatography (AcEt:Hept/1:3) afforded the product as a brown powder (150 mg, 44%). S6
1 H MR (300 MHz, CD 3 D) δ 7.95 (d, J = 6.8, Hz, 1H), 7.64 (d, J = 9.2, Hz, 1H), 7.21 (m 1H), 6.84 (t, J = 6.8, Hz, 1H), 3.37 (t, J = 6.5 Hz, 2H), 3.12 (t, J = 6.5 Hz, 2H), 1.46 (m, 2H), 1.76 (m, 4H), 1.25 (m, 2H), 1.10 (m, 6H). 13 C MR (75 MHz, CDCl 3 ) δ 202.6, 143.7, 142.2, 126.2, 125.3, 124.4, 119.4, 113.7, 39.2, 27.3, 25.9, 25.2, 23.8, 23.5, 23.4, 22.4, 20.2. HRMS-ESI+: m/z [M + H]+ calcd for C 17 H 23 2 : 271.1810; found : 271.1825 X-Ray Crystallography X-ray Experimental for 3aj Crystals grew as colorless cobblestones by slow evaporation from methanol. The data crystal had approximate dimensions: 0.20 0.20 0.1 mm. The data were collected at room temperature on a XtaLabPro Rigaku diffractometer using an HPAD Pilatus 200K detector and a microfocus sealed tube mm003 with integrated confocal caxflux double bounce optic with MoKα radiation (λ = 0.71075 A ). A total of 574 frames of data were collected using ω-scans with a scan range of 0.5 and a counting time of 20 seconds per frame. Details of crystal data, data collection and structure refinement are listed in Table S1. Data reduction were performed using CrystalClear-SM Expert 2.1 b45 1. The structure was solved by direct methods using SHELXT 2 and refined by full-matrix least-squares on F 2 with anisotropic displacement parameters for the non-h atoms using SHELXL- 2014/7 3. Structure analysis was aided by use of the programs PLAT 4 and SHELXL- 2014/7. All non-h atoms were refined anisotropically; H atoms were fixed in geometrically estimated positions using the riding model. The cyclohexenone group displayed disorder at the level of the C4 atom, which was split over two sites, then the refined occupancy factors converged at 0.649(11) and 0.351(11) values. Since the CF3 group exhibited rather elongated displacement ellipsoids, the approach to treat the disorder was to refine the CF3 group split in two parts as rotating about the C10-C12 bond with F atoms 60 apart. nce distance (SADI) and rigid-bond (RIGU) restraints were employed, the occupancy ratios of the two components, freely refined, converged at very uneven values, 0.944(3) and 0.056 (3). The structure model with a resulting CF3 circular toroid nonetheless benefited from this approach, with residual electron density much lower between the F atoms. The function, Σw( F o 2 - F c 2 ) 2, was minimized, where w = 1/[(σ(F o )) 2 + (0.0828*P) 2 + (0.1798*P)] and P = ( F o 2 + 2 F c 2 )/3. Rw(F 2 ) refined to 0.1519, with R(F) equal to 0.0615 and a goodness of fit, S, = 1.081. Definitions used for calculating R(F), Rw(F 2 ) and the goodness of fit, S, are given below 5. Thermal ellipsoid plot (see Fig. S7
S??) was generated using RTEP III 6 as implemented in PLAT. Tables of positional and thermal parameters, bond lengths and angles, torsion angles and figures may be obtained from the Cambridge Crystallographic Centre by referencing CCDC number 1430186. Table S1. Crystal data and structure refinement for compound 3aj. Identification code compound 3aj Empirical formula C 12 H 9 F 3 2 Formula weight 254.21 Temperature 293(2) K Wavelength 0.71075 Å Crystal system Monoclinic Space group P2 1 /c Unit cell dimensions a = 9.3458(7) Å α= 90. b = 13.3878(10) Å β= 104.592(7). c = 9.0150(7) Å γ = 90. Volume 1091.57(15) Å 3 Z 4 Density (calculated) 1.547 Mg/m 3 Absorption coefficient 0.136 mm -1 F(000) 520 Crystal size 0.20 x 0.20 x 0.10 mm 3 θ range for data collection 3.837 to 27.489. Index ranges -12 h 12, -17 k 17, -11 l 11 Reflections collected 12009 Independent reflections 2481 [R(int) = 0.0288] Completeness to θ = 25.242 98.9 % Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.986 and 0.860 Refinement method Full-matrix least-squares on F 2 Data / restraints / parameters 2479 / 66 / 201 Goodness-of-fit on F 2 1.081 Final R indices [I>2σ(I)] R1 = 0.0487, wr2 = 0.1413 R indices (all data) R1 = 0.0615, wr2 = 0.1519 Extinction coefficient n/a Largest diff. peak and hole 0.291 and -0.257 e.å -3 S8
1. Rigaku. CrystalClear-SM Expert 2.1 b45. A program for X-ray diffraction data collection. Rigaku Corporation, The Woodlands, Texas, USA(2015). 2. Sheldrick, G.M. SHELXT. A program for crystal structure solution. Acta Cryst. A71, 3-8 (2015). 3. Sheldrick, G.M. SHELXL-2014/7. Program for the refinement of crystal structures. Acta Cryst. C71, 3-8 (2015). 4. Spek, A.L. PLAT, a multipurpose crystallographic tool. Acta Cryst. D65, 148-155(2009). 5. Rw(F 2 ) = {Σw( F o 2 - F c 2 ) 2 /Σw( F o ) 4 } 1/2 where w is the weight given each reflection. R(F) = Σ( F o - F c )/Σ F o } for reflections with F o > 4(σ(F o )).S = [Σw( F o 2 - F c 2 ) 2 /(n - p)] 1/2, where n is the number of reflections and p is the number of refined parameters. 6. Burnett, M.. & Johnson, C. K. RTEPIII. Report RL-6895. ak Ridge ational Laboratory, Tennessee, USA(1996). Figure S. Displacement ellipsoid plot of the asymmetric unit from the single crystal structure of???. Disorder is omitted for clarity; ellipsoids displayed at 50 % probability level. S9
8,9-Dihydrobenzo[4,5]imidazo[1,2-a]pyrimidin-6(7H)-one (3aa) S10
9-Methyl-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyrimidin-6(7H)-one (3ba) (EL174B, B3434) S11
9-(tert-Butyl)-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyrimidin-6(7H)-one (3ca) S12
8,9-Dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ab) S13
3-Fluoro-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ac) S14
2-Chloro-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ad) S15
2-Bromo-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ae) S16
3-Bromo-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3af) S17
4-Bromo-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ag) S18
6-oxo-6,7,8,9-tetrahydrobenzo[4,5]imidazo[1,2-a]pyridine-3-carbonitrile (3ah) S19
3-(Trifluoromethyl)-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3ai) S20
2-(Trifluoromethyl)-8,9-dihydrobenzo[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3aj) S21
7,8,9,10-Tetrahydro-6H-cyclohepta[4,5]imidazo[1,2-a]pyridin-6-one (3eb) S22
8,9,10,11-Tetrahydrocycloocta[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3fb) S23
8,9,10,11-Tetrahydrocyclododeca[4,5]imidazo[1,2-a]pyridin-6(7H)-one (3gb) S24