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1 Supporting Information Activation of Ene-Diamido Samarium Methoxide with Hydrosilane for Selectively Catalytic Hydrosilylation of Alkenes and Polymerization of Styrene: an Experimental and Theoretical Mechanistic Study Jianfeng Li, Chaoyue Zhao, Jinxi Liu, Hanmin Huang, Fengxin Wang, Xiufang Xu*, and Chunming Cui*,, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin ; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin , P. R. China Homepage: S1

2 Table of Contents General Experimental Kinetic Studies X-ray Diffraction Parameters and Data Computational Details Reference NMR Spectra of LK2 and 1 NMR Spectra of Hydrosilylation Product Spectra of sps NMR Spectra of Crude Hydrosilylation Reaction Mixtures GC-MS Spectra of Crude Hydrosilylation Reaction Mixtures S3 S6 S8 S9 S70 S71 S73 S75 S78 S83 S2

3 General Experimental All manipulations involving air- and moisture-sensitive compounds were carried out under an atmosphere of dry argon by using modified Schlenk line and glovebox techniques. Elemental analyses were carried out on an Elementar Vario EL analyzer. EI-MS were recorded on VG ZAB-HS. The 1 H, 13 C, and 29 Si NMR spectroscopic data were recorded on a Bruker AV400 spectrometer. GC-MS data were obtained with a Thermo Scientific TRACE 1300 & ISQ QD system, equipped with a TG-5MS column. Infrared spectra were recorded on a Bio-Rad FTS 6000 spectrophotometer. Gel permeation chromatography (GPC) analyses of the molecular weight and molecular weight distribution were performed on a Waters 1525 instrument using standard polystyrene as calibration and with THF as the eluent at 25 C. The solvents (DME, THF, toluene, and n-hexane) were freshly distilled from sodium and degassed prior to use. α-diimine, LH2 and Sm[N(SiMe3)2]2(THF)2 were synthesized according to the published procedures. S1,S2 Alkenes and dienes were vacuum-distilled over CaH2 and then were degassed prior to use. Other chemicals were of analytical grade and were used as received. Synthesis of LK 2. A mixture of potassium (160 mg, 4 mmol) and α-diimine (808 mg, 2 mmol) in DME (30 ml) was stirred at room temperature for 3 days. The volatiles were removed under vaccum. The remaining residue was washed by n-hexane and subsequently dried under vaccum to yield red powder of LK2 (996 mg, 87%). Mp: 231 C dec. 1 H NMR (THF-d8, 400 MHz, 23 C): δ 1.03 (d, 3 JHH = 6.9 Hz, 12H, CHMe2), 1.21 (d, 3 JHH = 6.8 Hz, 12H, CHMe2), 1.66 (s, 6H, CMe), 3.67 (sept, 3 JHH = 6.8 Hz, 4H, CHMe2), 5.97 (t, 3 JHH = 7.3 Hz, 2H, Ar-H), 6.63 (d, 3 JHH = 7.3 Hz, 4H, Ar-H). 13 C NMR (THF-d8, 101 MHz, 23 C): δ (CHMe2), (CMe), (CHMe2), 59.06, (DME-C), (CMe), , , , (Ar-C). Synthesis of 1. Amine Elimination Method: A mixture of Sm[N(SiMe3)2]2(THF)2 (1.230 g, 2 mmol) and LH2 (812 mg, 2 mmol) was added 30 ml DME. The solution was stirred at room temperature for 20 h. The solution was concentrated to 5 ml. Storage at 35 C overnight afforded brown crystals of 1 (613 mg, 46%). Salt Metathesis Method: A solution of SmI2(THF)2 (1.096 g, 2 mmol) in DME was added freshly S3

4 prepared LK2 (2 mmol) in DME. The solution was stirred at room temperature for 20 h. After removing the solvent under reduced pressure, the residue was extracted by toluene. The filtrate was concentrated to 5 ml. Storage at 35 C overnight afforded brown crystals of 1 (1.137 g, 84%). Mp: C. Anal. Calcd for C66H106N4O6Sm2 ( ): C, 58.62; H, 7.90; N, Found: C, 58.34; H, 7.60; N, is paramagnetic. 1 H NMR (C6D6, 400 MHz, 23 C): δ 3.56 (s, 8H, DME-H), 1.70 (s, 12H, DME-H), 1.59 (s, 12H, DME-H), 0.49 (s, 8H, DME-H), 1.34 (d, 3 JHH = 6.5 Hz, 12H, CHMe2), 2.29 (s, 12H, CMe) 3.03 (d, 3 JHH = 6.4 Hz, 12H, CHMe2), 3.29 (d, 3 JHH = 6.2 Hz, 12H, CHMe2), 3.95 (d, 3 JHH = 6.3 Hz, 12H, CHMe2), 4.44 (s, 6H, OMe), 5.17 (d, 3 JHH = 7.5 Hz, 2H, Ar-H), 6.12 (t, 3 JHH = 7.4 Hz, 4H, Ar-H), 6.35 (d, 3 JHH = 7.5 Hz, 2H, Ar-H), 7.34 (t, 3 JHH = 7.5 Hz, 2H, Ar-H), 7.97 (d, 3 JHH = 7.6 Hz, 2H, Ar-H), 9.25 (sept, 3 JHH = 6.7 Hz, 4H, CHMe2), (sept, 3 JHH = 6.6 Hz, 4H, CHMe2). 13 C NMR (THF-d8, 101 MHz, 23 C): δ 14.60, 18.96, 20.94, 21.86, 22.31, 24.43, 25.47, 26.67, 27.23, 27.55, 29.06, 29.20, 29.54, 30.08, 31.03, 32.57, 59.06, 67.57, 72.84, , , , , , , , , , , , , , Typical Procedure for Catalytic Hydrosilylation. In an Ar glove box, a Schlenk tube was charged with catalyst (2.5 mol %) and solvent (1 ml). And then PhSiH3 (1 mmol) and the appropriate alkene or diene (1 mmol) were added by microsyringe. The Schlenk tube was quickly removed from the glovebox. The reaction mixture was stirred at 60 C using oil bath. The reaction was monitored by 1 H NMR spectroscopy. After the reaction was complete, the product was purified by column chromatography on silica gel (n-hexane for elution) to yield colorless oil. The spectra of hydrosilylated products 3a, S3 3c, S3 3d, S4 3e, S5 3f, S3 3g, S3 3h, S3 and 3i S6 were consistent with literature. 3b (210 mg, 96% of yield): 1 H NMR (C6D6, 400 MHz, 23 C): δ 1.36 (d, 3 JHH = 7.5 Hz, 3H, CHMe), 2.12 (s, 3H, Ar-Me), 2.43 (m, 1H, SiH2CH), 4.51 (m, SiH2), (m, 9H, Ar-H). 13 C NMR (C6D6, 101 MHz, 23 C): δ (CHMe), (Si-C), (Ar-Me), , , , , , , , (Ar-C). 29 Si NMR (C6D6, 79 MHz, 23 C): δ EI-MS, m/z S4

5 Regioselectivity were analysed by GC-MS of the crude reaction mixture, after quenching and diluting the crude reaction mixture with n-hexane. Typical Procedure for Catalytic Polymerization. In an Ar glove box, a Schlenk tube was charged with catalyst ( mmol) and toluene (0.5 ml). And then PhSiH3 (0.5 mmol) and styrene (5 mmol) were added by microsyringe sequentially. The Schlenk tube was quickly removed from the glovebox. The reaction mixture was stirred at 60 C using oil bath. The reaction was quenched by addition of methanol after 6 h. The polymer was collected by filtration and then washed by methanol three times, followed by drying uder high vacuum. White solid (369 mg, 71% of yield). The syndiotacticity is > 99% by 1 H and 13 C NMR. Mn = 5100, PDI = 1.33 by GPC. 1 H NMR (relative intensity, CDCl3, 400 MHz, 23 C): δ 0.95 (2.3, CHMe), 1.37 (66, CH2), 1.82 (33, CH), 4.08 (1.5, SiH2), 6.60 (66, Ar-H), 7.11 (100, Ar-H). 13 C NMR (CDCl3, 101 MHz, 23 C): δ 23.8, 40.7, 44.0, 125.8, 127.8, 128.0, Si NMR (CDCl3, 79 MHz, 23 C): δ IR (cm 1 ): ṽ 2130 (Si H). S5

6 Kinetic Studies Table S1. Measurement of the 1-hexene concentration in different catalyst concentrations during the hydrosilylation process. [a] entry [catalyst] (M) time (min) ln([hexene]/[hexene] 0 ) 10 5 k obs (s 1 ) [a] In an Ar glove box, four NMR tubes were charged with 1 (10 20 mg, 7 15 μmol), PhSiH 3 (308 μl, 2.5 mmol) and 1-hexene (31 μl, 0.25 mmol). Then C 6 D 6 was added to bring the total volume of the solution to 0.5 ml. The tubes were closed and shaken vigorously, then quickly removed from the glovebox. The reaction mixtures were maintained at 23 C and were recorded by 1 H NMR spectroscopy at regular intervals. The concentration of 1-hexene during the reaction was determined by the integrals of 1-hexene (δ 5.74 ppm) standardized to the total integrals of 1-hexene and hydrosilylated product 3f (δ 4.51 ppm). S6

7 Table S2. Measurement of the 1-hexene concentration in different PhSiH3 concentration during the hydrosilylation process. [a] entry [PhSiH 3 ] (M) time (min) ln([hexene]/[hexene] 0 ) 10 5 k obs (s 1 ) [a] In an Ar glove box, three NMR tubes were charged with 1 (8 mg, 6 μmol), PhSiH 3 ( μl, mmol) and 1-hexene (31 μl, 0.25 mmol). Then C 6 D 6 was added to bring the total volume of the solution to 0.5 ml. The tubes were closed and shaken vigorously, then quickly removed from the glovebox. The reaction mixtures were maintained at 23 C and were recorded by 1 H NMR spectroscopy at regular intervals. The concentration of 1-hexene during the reaction was determined by the integrals of 1-hexene (δ 5.74 ppm) standardized to the total integrals of 1-hexene and hydrosilylated product 3f (δ 4.51 ppm). S7

8 X-ray Diffraction Parameters and Data All intensity data were collected with a Bruker SMART CCD diffractometer, using graphite-monochromated Mo Kα radiation (λ = Å). The structures were resolved by direct methods and refined by full matrix least squares on F 2. S7 Hydrogen atoms were considered in calculated positions. All non-hydrogen atoms were refined anisotropically. The ORTEP-3 program was utilized to draw the molecules. S8 Crystal data and data collection details are collected in Tables S3. Crystals of 1 suitable for X-ray analysis was obtained from DME at 35 C. CCDC (1) contains the supplementary crystallographic data for this paper. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via Table S3. Crystallographic detail for 1. 1 formula C 66 H 106 N 4 O 6 Sm 2 (C 4 H 10 O 2 ) Fw T (K) 113(2) space group P 2 1 /n a (Å) (3) b (Å) (3) c (Å) (4) α ( ) 90 β ( ) (3) γ ( ) 90 V (Å 3 ) (13) Z 2 d calcd (g/cm 3 ) F(000) 1504 GOF R 1, wr 2 (I>2σ(I)) , R 1, wr 2 (all data) , CCDC S8

9 Computational Methods Geometry optimizations were performed with the B3LYP S9 functional. The large core ECP51MWB S10 optimized by the Stuttgart/Cologne group was used for samarium centers, and the 6-31G(d) basis set was employed for other atoms. Frequency calculations were performed at K to verify that the stationary points were the local minima or first-order saddle points, i.e., transition states, and to obtain thermal corrections. Intrinsic Reaction Coordinate (IRC) S11 calculations were performed to determine the connectivity of the minima and transition states. Single point energy calculations were performed with the M06 functional, S12 a mixed basis set of ECP51MWB S10 for samarium and G(d,p) for other atoms, and the SMD S13 solvation model with toluene as the solvent (ε= ). All the reported Gibbs free energy values are the sum of the electronic energy from the single point calculations and the thermal corrections obtained by the frequency calculations. All of the calculations were performed with Gaussian 09. S14 S9

10 Figure S1. Gibbs free energies of the transition states for the hydrosilylation and polymerization of styrene. Figure S2. The Gibbs free energy profiles of the 1-catalyzed hydrosilylation of propene along other possible pathways involving samarium silyl intermediate. Energies are calculated using M06/ECP51MWB G(d,p)/SMD(toluene)//B3LYP/ECP51MWB-6-31G(d) method. S10

11 The Cartesian Coordinates of the stationary points discussed in the text For transition state structures, one imaginary frequency was observed and given below. For all minimum structures, no imaginary frequency was observed. 4 Atom X Y Z O O N N C C C C C H H H C H H H C C C C H H C H C C H H H C H H H C S11

12 H C H H H C H C H H C H C H C H C H C H C H C H H H C H H H C H H H C H H H C H S12

13 C H H H C H H H C H H H O C H H H Sm TS Imaginary frequency: cm -1 Atom X Y Z N N C C C C C H H H C C C C H C C S13

14 H H H C H H H C H H H C H C H C H C H C H C H C H C H C H H H C H H H C H H H C S14

15 H H H C H C H H H C H H H C H H H Sm C C C C H C H C H H H O H Si H H Atom X Y Z N N C S15

16 C C C C H H H C C C C H C C H H H C H H H C H H H C H C H C H C H C H C H C H C S16

17 H C H H H C H H H C H H H C H H H C H C H H H C H H H C H H H Sm C C C C H C H C S17

18 H H H O Si H H H A (catalyst) Atom X Y Z O O N N C C C C C H H H C H H H C C C C H H C H C C H H H S18

19 C H H H C H C H H H C H C H H C H C H C H C H C H C H C H H H C H H H C H H H C S19

20 H H H C H C H H H C H H H C H H H Sm H DME Atom X Y Z O O C H H H C H H C H H H C H H PhSiH 3 S20

21 Atom X Y Z Si H H H C C C C H C H C H H H MeOSiH 2 Ph Atom X Y Z C H H H C C C C H C H C H H H O Si H H propene S21

22 Atom X Y Z C H H C H C H H H styrene Atom X Y Z C C C C C C H H H H H C H C H H prod (product) Atom X Y Z C C C C H C H C S22

23 H H H C H H H C H C H H Si H H H A Atom X Y Z Sm N N C C C C C H H H C C C C H C C H H H S23

24 C H H H C H C H C H C H C H C H C H C H C H H H C H H H C H H H C H H H C H C H S24

25 H H C H H H C H H H C H C H H C H H H H R-TS1-B Imaginary frequency: cm -1 Atom X Y Z Sm N N C C C C C H H H C C C C S25

26 H C C H H H C H H H C H C H C H C H C H C H C H C H C H H H C H H H C H H H C H S26

27 H H C H C H H H C H H H C H H H C C H H H H C H H H R-TS1-L Imaginary frequency: cm -1 Atom X Y Z Sm N N C C C C C H S27

28 H H C C C C H C C H H H C H H H C H C H C H C H C H C H C H C H C H H H C H H H S28

29 C H H H C H H H C H C H H H C H H H C H H H C H C H H H C H H H Ph-TS1-B Imaginary frequency: cm -1 Atom X Y Z Sm N N S29

30 C C C C C H H H C C C C H C C H H H C H H H C H C H C H C H C H C H C H C H C H S30

31 H H C H H H C H H H C H H H C H C H H H C H H H C H H H C C H H H H C C C C H C S31

32 H C H H H Ph-TS1-L Imaginary frequency: cm -1 Atom X Y Z Sm N N C C C C C H H H C C C C H C C H H H C H H H C H C H C S32

33 H C H C H C H C H C H C H H H C H H H C H H H C H H H C H C H H H C H H H C H H S33

34 H C H C H H H C C C C H C H C H H H B Atom X Y Z Sm N N C C C C C H H H C C C C H C C H S34

35 H H C H H H C H C H C H C H C H C H C H C H C H H H C H H H C H H H C H H H C H S35

36 C H H H C H H H C H H H C H H C H H H C H H R-TS2-L Imaginary frequency: cm -1 Atom X Y Z Sm N N C C C C C H H H C C S36

37 C C H C C H H H C H H H C H C H C H C H C H C H C H C H C H H H C H H H C H H H S37

38 C H H H C H C H H H C H H H C H H H C H H H C H H C C C C H C H C H H H H C H H S38

39 Si H H B Atom X Y Z Sm N N C C C C C H H H C C C C H C C H H H C H H H C H C H C H C H C S39

40 H C H C H C H C H H H C H H H C H H H C H H H C H C H H H C H H H C H H H C H H S40

41 H C H H C C C C H C H C H H H H C H H Si H H Atom X Y Z N N C C C C C H H H C C C C H S41

42 C C H H H C H H H C H H H C H C H C H C H C H C H C H C H C H H H C H H H C H H S42

43 H C H H H C H C H H H C H H H C H H H Sm C C C C H C H C H H H O Si H H H TS3 Imaginary frequency: cm -1 S43

44 Atom X Y Z N N C C C C C H H H C C C C H C C H H H C H H H C H H H C H C H C H C H C H C S44

Supporting Information

Supporting Information Manuscript Title: Synthesis of Semibullvalene Derivatives via Co 2 (CO) 8 -Mediated Cyclodimerization of 1,4-Dilithio-1,3-butadienes Corresponding Author: Zhenfeng Xi Affiliations: