Supporting Information

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1 1 Supporting Information Early-Late Heterobimetallic Complexes as Catalyst for Ethylene Polymerization. Cooperative Effect of Two Metal Centers to Afford Highly Branched Polyethylene Junpei Kuwabara, Daisuke Takeuchi, and Kohtaro Osakada* General Methods. All the manipulations of the air unstable complexes were carried out under nitrogen or argon using standard Schlenk techniques. Toluene, hexane, Et 2 O, and THF were distilled from sodium benzophenone ketyl and stored under nitrogen or argon. CH 2 2 were distilled from CaH 2 and stored under nitrogen or argon. MMAO was purchased from TOSOH-FINECHEM and stored under nitrogen or argon. Zirconium tetrachloride and other chemicals were used as received from commercial suppliers. C 5 Me 4 H-SiMe 2 -C 5 H 5 1 and 6-hydroxymethyl-2-pyridinecarboxaldehyde2 were prepared according to the literature method. NMR spectra (1H and 13C{1H}) were recorded on JEOL JNM LA-500 or Varian Mercury 300 spectrometers. Assignment of the NMR signals is shown in Chart 1. Si c a d b e Zr H f1 f H f2 H a1 H a2 a b c O O f e d g N Pd p h i o j l N k q m n Si c a d b e Zr f g O O j i h k N Pd l t m s n N o p u q r Chart 1 Elemental analyses were carried out with a Yanaco MT-5 CHN autocorder. Gel permeation chromatography (GPC) was performed on a TOSOH HPLC-8121GPC/HT using orthodichlorobenzene (152 ºC) as eluent for polyethylene and TOSOH HPLC-8220

2 2 using THF as eluent for ethylene oligomer. DSC and TG were recorded on Seiko DSC6200R and Seiko TG/DTA6200R instruments, respectively. Crystal Structure Determination. Crystals of 6 suitable for X-ray diffraction study was obtained by recrystallization from CH22/benzene at 3 C and mounted in glass capillary. The data for 6 were collected at a temperature of C to a maximum 2θ value of 55.0 on Rigaku Saturn CCD area detector. Calculations were carried out by using a program package CrystalStructureTM for Windows. The structure was solved by direct method and expanded using Fourier techniques. A full matrix least-squares refinement was used for non-hydrogen atoms with anisotoropic thermal parameters. Atomic scattering factors were obtained from the literature. 3 Preparation of (η 5 -C5Me4-SiMe2-η 5 -C5H3CH2CH=CH2)Zr2 (1) To a solution of C5Me4H-SiMe2-C5H5 (2.69 g, 11.0 mmol) in THF (80 ml) was added n-buli in hexane (1.6 M, 7.30 ml, 11.6 mmol) dropwise at 78 ºC. After the solution was stirred for 6 h at room temperature, 3-bromo-1-propene (1.40 g, 11.6 mmol) was added dropwise to the reaction mixture. After the mixture was stirred for 15 min, aqueous solution of NH4 was added. Organic layer was extracted with Et2O and washed with H2O and dried over Na2SO4. The mixture was purified by chromatography on alumina with hexane as an eluent to give C5Me4H-SiMe2-C5H4CH2CH=CH2 as pale yellow oil (2.59 g, 83%). To a solution of C5Me4H-SiMe2-C5H4CH2CH=CH2 (2.58 g, 9.1 mmol) in THF (60 ml) was added n-buli in hexane (1.6M, 11.9 ml, 19.0 mmol) dropwise at 78 ºC. The mixture was stirred for 6 h at room temperature. After the pale yellow solution was evaporated, Zr4 (2.12 g, 9.1 mmol) and toluene (150 ml) was added at 78 C. The mixture was allowed to warm up to room temperature over 1 h. After the

3 3 mixture was stirred for 24 h, the resulting brown solution was evaporated and extracted with hexane. The product was purified by recrystallization from hexane at 30 ºC to give 1 (1.08 g, 27%). 1 H NMR (300 MHz, CD3): δ 6.74 (t, 1H, J=2 Hz, Ha-c), 6.04 (dddd, 1H, 3 J=17, 10, 7, 6 Hz, H e), 5.39 (t, 1H, J=2 Hz, Ha-c), 5.12 (t, 1H, J=2 Hz, Ha-c), 5.02 (dq, 1H, 3 J=17 Hz, 3 J= 4 J= 2 Hz, Hf1), 5.00 (m, 1H, Hf2), 3.62 (dd, 1H, 2 J=16 Hz, 3 J= 6 Hz, Hd), 3.50 (dd, 1H, 2 J=16 Hz, 3 J=7 Hz, Hd), 2.03, 2.00, 1.71, 1.63 (s, 3H, C5Me4), 0.37, 0.34 (s, 3H, SiMe2). 13 C{ 1 H} NMR (75 MHz, CD3): δ (s, Cipso), (s, Ce), (s, Cipso), (s, Cipso), (s, Ca-c), (s, Cipso), (s, Cipso), (s, Cf), (s, Ca-c), (s, Ca-c), (s, Cipso), 97.0 (s, Cipso),.34.8 (s, Cd), 15.0, 14.8, 12.4, 12.3 (s, C5Me4), 0.70, (s, SiMe2). Anal. Calcd. for C19H242SiZr : C, 51.33; H, 5.89;, Found : C, 51.16; H, 5.69;, Preparation of 2-Propenoicacid 6-(2-formyl)pyridyl methyl ester To a solution of 6-hydroxymethyl-2-pyridinecarboxaldehyde (480 mg, 3.5 mmol) in CH22 (12 ml) and NEt3 (1.1 ml) was added acroyl chloride (0.34 ml, 4.2 mmol) dropwise at 0 ºC. The solution was stirred for 3 h at room temperature. After water was added to the mixtre, separated organic layer was washed with H2O, brine and was dried over Na2SO4. The mixture was purified by chromatography on silica gel (5 wt% H2O) with mixture of hexane and ethyl acetate (2:1) as an eluent to give 2-Propenoicacid 6-(2- formyl)pyridyl methyl ester as pale yellow oil (595 mg, 72%). 1 H NMR (300 MHz, CD3): δ 10.1 (s, 1H, CHO), 7.91 (dd, 1H, J 3 = 4 Hz, J 4 = 1 Hz, CH in pyridyl group), 7.90 (dd, 1H, J 3 = 5 Hz, J 4 = 1 Hz, CH in pyridyl group), 7.61 (dd, 1H, J 3 = 5 Hz, J 3 = 4 Hz, CH in pyridyl group), 6.53 (dd, 1H, J 3 = 17 Hz, J 2 = 1 Hz, CH2=CH trans), 6.25 (dd, 1H, J 3 = 17 Hz, J 3 = 11 Hz, CH2=CH), 5.93 (dd, 1H, J 3 = 11 Hz, J 2 = 1 Hz, CH2=CH cis), 5.42 (s, 2H, CH2). 13 C{ 1 H} NMR (75 MHz, CD3): δ (s, CHO), (s,

4 4 CH2=CHC(O)), (s, Cipso), (s, Cipso), (s, CH2=CH), (s, CH in pyridyl group), (s, CH2=CH), (s, CH in pyridyl group)), (s, CH in pyridyl group), 66.1 (s, CH2). Preparation of Pd complex 2. To a solution of 2-propenoicacid 6-(2-formyl)pyridyl methyl ester (90.6 mg, 0.47 mmol) in EtOH (6 ml) was added 2,6-diisopropyl aniline (0.18 ml, 0.95 mmol). After the solution was stirred for 15 h at room temperature, volatiles were evaporated to give yellow oil. THF (20 ml) and Pd2(cod) were added to the oil product. After the solution was stirred for 36 h at room temperature, volatiles were evaporated. A yellow residue was washed with hexane (10 ml X 3) and was recrystallized from CH22/hexane to give 2 as a pale yellow solid (162 mg, 68%). 1 H NMR (300 MHz, CD3): δ 8.16 (t, 1H, J = 8 Hz, Hg), 8.11 (s, 1H, Hj), 7.79 (d, 1H, J 3 = 8 Hz, Hf or h), 7.78 (d, 1H, J 3 = 8 Hz, Hf or h), 7.35 (t, 1H, J = 8 Hz, Hn), 7.19 (d, 2H, J 3 = 8 Hz, Hm), 6.57 (dd, 1H, J 3 = 17 Hz, J 2 = 1 Hz, Ha2), 6.26 (dd, 1H, J 3 = 17 Hz, J 3 = 10 Hz, Hb), 6.14 (s, 2H, Hd), 6.00 (dd, 1H, J 3 = 10 Hz, J 2 = 1 Hz, Ha1), 3.32 (quint, 1H, J 3 = 7 Hz, Ho), 1.41 (d, 6H, J 3 = 7 Hz, Hp or q), 1.14 (d, 6H, J 3 = 7 Hz, Hp or q). 13 C{ 1 H} NMR (75 MHz, CD3): δ (s, Cj), (s, Cc), (s, Ci or e), (s, Ck), (s, Ci or e), (s, Cg), (s, ), (s, Ca), (s, Cf or h), (s, Cb), (s, Cf or h), (s, Cn), (s, Cm), 66.3 (s, Cd), 29.0 (s, Co), 24.8 (s, Cp or q), 23.3 (s, Cp or q). Anal. Calcd. for C22H26N22O2Pd: C, 50.07; H, 4.97; N, 5.31;, Found : C, 49.92; H, 5.17; N, 5.09;, Preparation of 3 and 4 were conducted in a similar manner to that of 2 from NiBr2(H2O)3 and Co2 instead of Pd2(cod), respectively.

5 5 3 (68% yield): Anal. Calcd. for C22H28N2Br2O3Ni: C, 45.02; H, 4.81; N, 4.77; Br, Found : C, 45.26; H, 4.50; N, 4.81; Br, (58% yield): Anal. Calcd. for C22H26N22O2Co: C, 55.02; H, 5.46; N, 5.83;, Found : C, 54.65; H, 5.42; N, 5.72;, Preparation of Zr-Pd heterobimetallic complex 5. A CH22 (2.0 ml) solution of 1 (88.9 mg, 0.20 mmol), 2 (52.7 mg, 0.10 mmol), and 2Ru(=CHPh){CN(Mes)CH2CH2N(Mes)}(PCy3) (4.2 mg, 5.0 μmol) was stirred for 24 h at room temperature. After evaporation of volatiles, residue was washed with Et2O (5 ml X 3). The product was purified by crystallization from CH22/ Et2O to give 5 (53.9 g, 57%). 1 H NMR (300 MHz, CD3): δ 8.14 (t, 1H, J = 8 Hz, Hk), 8.08 (s, 1H, Hn), 7.79 (d, 1H, J 3 = 8 Hz, Hj or l), 7.76 (d, 1H, J 3 = 8 Hz, Hj or l), 7.34 (t, 1H, J = 8 Hz, Hr), 7.25 (dt, 1H, J = 16 Hz, 7 Hz, He), 7.19 (d, 2H, J 3 = 8 Hz, Hq), 6.69 (t, 1H, J = 2 Hz, Ha-c), 6.14 (d, 1H, J = 17 Hz, Hh), 6.05 (d, 1H, J = 17 Hz, Hh), 5.96 (dt, 1H, J 3 = 16 Hz, J 4 = 2 Hz, Hf), 5.70 (t, 1H, J = 2 Hz, Ha-c), 5.37 (t, 1H, J = 2 Hz, Ha-c), 3.72 (ddd, 1H, J 2 = 17 Hz, J 3 = 7 Hz, J 4 = 2 Hz, Hd), 3.64 (ddd, 1H, J 2 = 17 Hz, J 3 = 7 Hz, J 4 = 2 Hz, Hd), 3.32 (quint, 1H, J 3 = 7 Hz, Hs), 2.09, 2.05, 1.96, 1.89 (s, 3H, C5Me4), 1.41 (d, 6H, J 3 = 7 Hz, Ht or u), 1.14 (d, 6H, J 3 = 7 Hz, Ht or u), 0.86, 0.84 (s, 3H, SiMe2). 13 C{ 1 H} NMR (75 MHz, CD3): δ (s, Cn), (s, Cg), (s, Ci or m), (s, Co), (s, Ce), (s, Ci or m), (s, Ck), (s, Cp), (s, Cipso), (s, Cipso), (s, Ca-c), (s, Cipso), (s, Cj or l), (s, Cj or l), (s, Cr), (s, Cipso), (s, Cipso), (s, Cq), (s, Cf), (s, Ca-c), (s, Cac), (s, Cipso), 97.8 (s, Cipso), 66.4 (s, Ch), 33.2 (s, Cd), 29.2 (s, Cs), 25.0 (s, Ct or u), 23.5 (s, Ct or u), 15.4, 15.3, 12.7, 12.6 (s, C5Me4), 0.01, 0.00 (s, SiMe2). Anal. Calcd. for

6 6 C39H48N24O2PdSiZr: C, 50.18; H, 5.44; N, 2.85;, Found : C, 49.94; H, 5.68; N, 3.04;, Preparation of 6 and 7 were conducted in a similar manner to that of 5 from 3 and 4, respectively. 6 (63% yield): Anal. Calcd. for C39H50N2Br22NiO3SiZr Et2O : C, 47.92; H, 5.61; N, 2.60; Br, 14.83;, Found : C, 48.31; H, 5.33; N, 2.66; Br, 15.11;, (48% yield): Anal. Calcd. for C39H48N24CoO2SiZr : C, 52.23; H, 5.39; N, 3.12;, Found : C, 52.03; H, 5.23; N, 3.06;, Preparation of 8-trimethylsilyl-1-octene. To a solution of trimethylsilyltrifluoromethanesulfonate (1.99 ml, 11 mmol) in THF (15 ml) was added THF solution of CH2=CH(CH2)6MgBr (1 M, 10 ml, 10 mmol) at -40 C. After the mixture was stirred for 12 h, aqueous solution of NH4 was added. The organic layer was extracted with Et2O and washed with H2O and brine, and dried over Na2SO4. The mixture was purified by fractional distillation (80 C, 4 mmhg) to give 8- trimethylsilyl-1-octene (910 mg, 46%). 1 H NMR (300 MHz, CD3): δ 5.82 (ddt, 1H, J = 17, 10, 6 Hz, olefinic), 4.99 (dd, 1H, J = 17, 1 Hz, olefinic), 4.93 (dd, 1H, J = 10, 1 Hz, olefinic), 2.04 (q, 2H, J 3 = 8 Hz, Hs), (m, 8H, CH2), 0.47 (t, 2H, J 3 = 6 Hz, CH2), (s, 9H, SiMe3). 13 C{ 1 H} NMR (75 MHz, CD3): δ (s, olefinic), (s, olefinic), 33.9, 33.5, 28.9, 28.9, 23.9, 16.7 (s, CH2), (s, SiMe3). Polymerization of Ethylene. Typical experimental procedure is as follows. MMAO (2.12 M-Al, 3.1 ml, 6.6 mmol-al) was added to 6 (6.5 mg, 6.6 μmol). The catalyst solution (2.1 mm-zr) was

7 7 stirred at room temperature for 15 min for the pre-activation. To a toluene (30 ml) saturated with ethylene (1 atm) was added the solution of the catalyst (2.4 ml, 5.0 μmol). The solution was stirred for 15 min under atmospheric ethylene at 50 C. The reaction was quenched with MeOH and 5 M H-MeOH. Separated polyethylene solid was filtrated, washed with MeOH, H2O, and hexane, and dried in reduced pressure. Copolymerization of Ethylene and 8-trimethylsilyl-1-octene. Typical experimental procedure is as follows. To a toluene (30 ml) saturated with ethylene (1 atm) was added 8-trimethylsilyl-1-octene (1 mmol) and the solution of the pre-activated catalyst (2.1 mm-zr, 2.4 ml, 5.0 μmol). The solution was stirred for 15 min under atmospheric ethylene at 50 C. The reaction was quenched with MeOH and 5 M H-MeOH. Separated polyethylene solid was filtrated, washed with MeOH, H2O, and hexane, and dried in reduced pressure. The number of branches is determined by intensity ratio of signal of trimethylsilyl group (0.10 ppm) in all signals in 1 H NMR spectra. Oligomerization of Ethylene by late transition metal catalyst. Typical experimental procedure is as follows. To a toluene (30 ml) saturated with ethylene (1 atm) was the solution of the pre-activated catalyst (2.1 mm-metal, 2.4 ml, 5.0 μmol). The consumption of ethylene was detected by mass flow meter (KOFLOC MODEL 3760) which is calibrated for ethylene. Reference 1) Stern, D.; Sabat, M.; Marks, T. J. J. Am. Chem. Soc. 1990, 112, ) Okuyama, Y: Nakano, H.; Kabuto, C.; Nozawa, E.; Takahashi, K.; Hongo, H. Heterocycles 2002, 58, 457.

8 8 3) International Tables for X-ray Crystallography; Kynoch: Birmingham, England, 1974; Vol. 4.

9 9 Si c a d b e Zr f O O j h k l t u N n s q Pd N r C 5 Me 4 Si-Me t, u * k n j,l e,r q a-c h f a-c a-c d * s δ * Et 2 O Figure S-1 1 H NMR spectrum of 5 (CD3, r.t.)

10 10 Figure S-2 13 C{ 1 H} NMR spectrum (C 2 D 2 4, 130 C) of polyethylene produced by 6 at 0 C (entry 3)

11 11 (a) 120 (b) log Mw log Mw (c) (d) log Mw log Mw Figure S-3 GPC profiles of polyethylenes (a: entry 2, b: entry 4, c: entry 5, d: entry 7)

12 12 Figure S-4 1 H NMR spectrum (C2D24, 130 C) of copolymer of ethylene and 8- (trimethylsilyl)-1-octene produced by 7.

13 13 Figure S-5 13 C{ 1 H} NMR spectra (C2D24, 130 C) of copolymer of ethylene and 8-(trimethylsilyl)-1-octene produced by 7.