Supporting Information Switching Selectivity of α-enolic dithioesters: One pot Access to Functionalized 1, 2- and 1, 3-Dithioles Suvajit Koley, Tanmoy Chanda, Subhasis Samai and Maya Shankar Singh*, Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi 221005, India Department of Chemistry, University Colleges of Science and Technology, University of Calcutta, 92, A.P.C. Road, Kolkata 700009, India 1. Synthesis of 2-(4-(4-Methoxybenzoyl)-5-(methylthio)-3H-1,2-dithiol-3-ylidene)-1-(4- methoxyphenyl)ethanone S2 2. Copies of the 1 H- and 13 C-NMR Spectra of the Compounds 3a-p and 4a-l S3-S30 3. ORTEP Diagrams of 3f and 4a S31 4. Crystals Descriptions S32-S33 S1
1. General Procedure for the Synthesis of 2-(4-(4-Methoxybenzoyl)-5-(methylthio)-3H- 1,2-dithiol-3-ylidene)-1-(4-methoxyphenyl)ethanone (5). In an 25 ml round-bottom flask α- enolic dithioester 1 (1.0 mmol) and PdCl 2 or Cu(OTf) 2 (0.2 mmol) were mixed and the reaction mixture was heated at 100 C. After 24 h, water (20 ml) was added to the reaction mixture followed by extraction with ethyl acetate (2 10 ml). The combined organic layer was dried over anhydrous Na 2 SO 4 and evaporated in vacuum. The crude residue was purified by column chromatography over silica gel using 8% ethyl acetate/hexane as eluent to afford mixture of E- and Z-isomers of 2-(4-(4-methoxybenzoyl)-5-(methylthio)-3H-1,2-dithiol-3- ylidene)-1-(4-methoxyphenyl)ethanone 5. As the synthesis of 2-(4-(4-methoxybenzoyl)-5- (methylthio)-3h-1,2-dithiol-3-ylidene)-1-(4-methoxyphenyl)ethanone 5 has done by our group (Ref. 22a and 22b of main manuscript), so we are not discussing in detail about these reaction. S2
2. Copies of the 1 H- and 13 C-NMR Spectra of the Compounds 3a-p and 4a-l 1 H NMR Spectrum of the Compound 3a: 13 C NMR Spectrum of the Compound 3a: S3
1 H NMR Spectrum of the Compound 3b: 13 C NMR Spectrum of the Compound 3b: S4
1 H NMR Spectrum of the Compound 3c: 13 C NMR Spectrum of the Compound 3c: S5
1 H NMR Spectrum of the Compound 3d: 13 C NMR Spectrum of the Compound 3d: S6
1 H NMR Spectrum of the Compound 3e: 13 C NMR Spectrum of the Compound 3e: S7
1 H NMR Spectrum of the Compound 3f: 13 C NMR Spectrum of the Compound 3f: S8
1 H NMR Spectrum of the Compound 3g: 13 C NMR Spectrum of the Compound 3g: S9
1 H NMR Spectrum of the Compound 3h: 13 C NMR Spectrum of the Compound 3h: S10
1 H NMR Spectrum of the Compound 3i: 13 C NMR Spectrum of the Compound 3i: S11
1 H NMR Spectrum of the Compound 3j: 13 C NMR Spectrum of the Compound 3j: S12
1 H NMR Spectrum of the Compound 3k: 13 C NMR Spectrum of the Compound 3k: S13
1 H NMR Spectrum of the Compound 3l: 13 C NMR Spectrum of the Compound 3l: S14
1 H NMR Spectrum of the Compound 3m: 13 C NMR Spectrum of the Compound 3m: S15
1 H NMR Spectrum of the Compound 3n: 13 C NMR Spectrum of the Compound 3n: S16
1 H NMR Spectrum of the Compound 3o: 13 C NMR Spectrum of the Compound 3o: S17
1 H NMR Spectrum of the Compound 3p: 13 C NMR Spectrum of the Compound 3p: S18
1 H NMR Spectrum of the Compound 4a (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4a (mixture of E/Z isomers): S19
1 H NMR Spectrum of the Compound 4b (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4b (mixture of E/Z isomers): S20
1 H NMR Spectrum of the Compound 4c (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4c (mixture of E/Z isomers): S21
1 H NMR Spectrum of the Compound 4d (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4d (mixture of E/Z isomers): S22
1 H NMR Spectrum of the Compound 4e (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4e (mixture of E/Z isomers): S23
1 H NMR Spectrum of the Compound 4f (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4f (mixture of E/Z isomers): S24
1 H NMR Spectrum of the Compound 4g (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4g (mixture of E/Z isomers): S25
1 H NMR Spectrum of the Compound 4h (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4h (mixture of E/Z isomers): S26
1 H NMR Spectrum of the Compound 4i (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4i (mixture of E/Z isomers): S27
1 H NMR Spectrum of the Compound 4j (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4j (mixture of E/Z isomers): S28
1 H NMR Spectrum of the Compound 4k (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4k (mixture of E/Z isomers): S29
1 H NMR Spectrum of the Compound 4l (mixture of E/Z isomers): 13 C NMR Spectrum of the Compound 4l (mixture of E/Z isomers): S30
3. ORTEP Diagrams of 3f and 4a ORTEP diagram of 3f: (ellipsoid contour probability level is 50%) ORTEP diagram of Z-isomer of 4a: (ellipsoid contour probability level is 50%) S31
4. Crystals Descriptions. Crystals suitable for X-ray single crystal analyses for 3f and 4a (Z-isomer) were obtained by slow diffusion of ethanol over a chloroform solution of the complex. X-ray data for 3f and 4a were collected on a 'Xcalibur, Eos' diffractometer with a fine-focus 1.75 kw sealed tube Mo Kα (λ = 0.71073 Å) X-ray source. Structures were solved by direct methods (SHELXS 97) and refined by full-matrix least squares on F 2 (SHELX 97). 1-3 All the non-h atoms were treated anisotropically. The H-atoms attached to aromatic carbon were included as fixed contribution and geometrically calculated and refined using SHELX riding model. Intermolecular interactions and stacking distances were analysed by using computer program PLATON. Table S1. Crystal data and structure refinement parameters for 3f 4a Empirical formula C 10 H 8 O S 3 C 19 H 14 O 2 S 3 Crystal system Monoclinic orthorhombic Space group P 1 21/n 1 P b c a a (Å) 7.5233(11) 12.232(5) b (Å) 13.4451(14) 8.022(5) c (Å) 10.8452(12) 35.840(5) α (deg) 90.00 90.00 β (deg) 104.929(13) 90.00 γ (deg) 90.00 90.00 V (Å 3 ), Z 1060.0(2), 4 3517(3), 8 λ (Å) 0.71073 0.71073 S32
Colour and habit Red, needle Yellow, needle T (K) 293(2) 150(2) reflns collected 5504 10366 refins/restraint/params 2410/0/131 4690/0/ 221 D calcd (Mg m -3 ) 1.506 1.399 µ (mm -1 ) 0.660 0.430 GOF on F 2 1.036 0.904 final R indices I>2σ(I) R1=0.0827 R1 = 0.0840 wr2 = 0.2057 wr2 = 0.1516 R indices (all data) R1 = 0.1166 R1 = 0.2886 wr2 = 0.2298 wr2 = 0.2472 Crystallisation Details: After collecting 4a (mixture of both the diastereomers) from the column, we dried it properly under vacuum. Then whole mixture taken in a vial and was dissolved in 5 ml chloroform and two drops of ethanol was added very carefully in upper surface of the solution (precaution has been taken as both the solvent should not mixed and ethanol should remain in the upper surface of chloroform layer). Then the vial was put around 18-20 C temperature for slow evaporation. After 6 days, we found some needle type crystals in the vial. We just picked up a crystal from the vial and performed single crystal XRD study. After obtaining the data, we found that the particular crystal belongs to Z-isomer of 4a. Crystallization of 3f is also done following the similar procedure to that of 4a. Reference: 1. Sheldrick, G. M.; Acta Cryst. A 2008, 64, 112. 2. Spek, A. L.; Acta Cryst. A 1990, 46, C31. 3. Spek, A. L.; PLATON, A Multipurpose Crystallographic Tools Utrecht University, Utrecht, The Netherlands, 2000. S33