Supplementary Material (ESI) for Chemical Communications
This journal is © The Royal Society of Chemistry 2000
Supplementary Materials
for
Grignard Reagent Mediated Reaction of Cp2Zr(II)-Ethylene Complex with Imines.
Tamotsu Takahashi,* Yuanhong Liu, Chanjuan Xi and Shouquan Huo
Catalysis Research Center and Graduate School of Pharmaceutical Sciences, Hokkaido University; and CREST, Science and Technology Corporation (JST), Sapporo 060-0811
All reactions involving organometallic compounds were carried out using standard Schlenk techniques under nitrogen. Tetrahydrofuran (THF) was dried over sodium and benzophenone. Zirconocene dichloride was purchased from Aldrich Chemical Co., Inc. n-Butyllithium (1.6M solution in hexane) and Grignard reagents were purchased from Kanto Chemicals Co., Ltd. Imines were prepared according to a literature.1
1H and 13C NMR spectra were recorded for CDCl3 (containing 1% TMS) solutions at 25_C on Bruker ARX-400 spectrometer. GC analysis was performed on SHIMADZU GC-14A equipped with fused silica capillary column SHIMADZU CBP1-M25-O25 and SHIMADZU C-R6A-Chromatopac integrator.
A typical procedure for zirconium catalyzed reactions of imines with EtMgBr: Formation of 4a.
A 20 ml Schlenk tube under dried nitrogen was charged with Cp2ZrCl2 (0.2 mmol, 58.5 mg), imine 3a (1 mmol, 195 mg) and THF (10 ml). The mixture was cooled to 0°C and then 1.00 M solutin of EtMgBr in THF (3 mmol, 3 ml) was added dropwise via syringe. The reaction mixture was stirred at r.t. for 1 h. GC analysis of an aliquot showed the formation of 4a in 95% yield after hydrolysis. The reaction mixture was quenched with water and extracted with ether (3x30 ml). The extract was washed with 20% NaHCO3, water, brine, water and dried over MgSO4. The solvent was evaporated in vacuo and the residue was purified by column chromatography on silica. A colorless liquid of 4a (158 mg, 70%) was obtained.
1-Phenylpropylbenzylamine (4a): A colorless liquid, 158 mg, yield 70% (GC 95%). 1H NMR (CDCl3, TMS) d 0.80 (t, J = 7.4 Hz, 3H), 1.61-1.77 (m, 3H), 3.50-3.54 (m, 2H), 3.64 (d, J =13.2 Hz, 1H), 7.18-7.34 (m, 10 H); 13C NMR (CDCl3, TMS) d 10.75 (CH3), 31.10 (CH2), 51.57 (CH2), 64.22 (CH), 126.77 (CH), 126.90 (CH), 127.43 (2CH), 128.12 (2CH), 128.30 (4CH), 140.83 (C), 144.10 (C). HRMS calcd for C16H19N 225.1516, found 225.1514.
1-Phenylpropylbutylamine (4b): A colorless liquid, 124 mg, yield 65% (GC 89%). 1H NMR (CDCl3, TMS) d 0.80 (t, J =7.4 Hz, 3H), 0.86 (t, J = 7.3, 3H), 1.21-1.48 (m, 5H). 1.55-1.81 (m, 2H), 2.34-2.49 (m, 2H), 3.45-3.48 (m, 1H), 7.20-7.32 (m, 5H). 13C NMR (CDCl3, TMS) d 10.81 (CH3), 14.00 (CH3), 20.50 (CH2), 31.05 (CH2), 32.50 (CH2), 47.55 (CH2), 65.28 (CH), 126.79 (CH), 127.32 (2CH), 128.22 (2CH), 144.50 (C). HRMS calcd for C13H21N 191.1673, found 191.1680.
1-tert-Butylpropylbenzylamine (4c): A colorless liquid, 137 mg, yield 67% (GC 97%). 1H NMR (CDCl3, TMS) d 0.91 (s, 9H), 0.99 (m, 4H), 1.04-1.21 (m, 1H), 1.64-1.70 (m, 1H), 2.03 (dd, J =8.7, 2.7 Hz, 1H), 3.78 (d, J =12.6 Hz, 1H), 3.88 (d, J =12.6 Hz, 1H), 7.20-7.37 (m, 5H). 13C NMR (CDCl3, TMS) d 12.73 (CH3), 24.57 (CH2), 26.97 (3CH3), 35.84 (C), 55.77 (CH2), 69.10 (CH), 126.77 (CH), 128.22 (2CH), 128.26 (2CH), 141.62 (C). HRMS calcd for C14H23N 205.1829, found 205.1832.
1-(2-Naphthylethyl)benzylamine (4d): A colorless oil, 238 mg, yield 87%. 1H NMR (CDCl3, TMS) d 0.80 (t, J =7.3 Hz, 3H), 1.67-1.81 (m, 3H), 3.53 (d, J =13.2 Hz, 1H), 3.62-3.67 (m, 2H), 7.14-7.80 (m, 12H). 13C NMR (CDCl3, TMS) d 10.77 (CH3), 30.92 (CH2), 51.55 (CH2), 64.28 (CH), 125.25 (CH), 125.37 (CH), 125.83 (CH), 126.46 (CH), 126.75 (CH), 127.62 (CH), 127.69 (CH), 128.08 (2CH), 128.14 (CH), 128.28 (2CH), 132.90 (C), 133.38 (C), 140.74 (C), 141.46 (C). HRMS calcd for C20H21N: 275.1673; found: 275.1663.
Stoichiometric reaction of imine 3c with zirconocene-ethylene complex 2
To a solution of Cp2ZrCl2 (0.29g, 1.0mmol) in THF (5ml) was added ethylmagnesium bromide (1.0M THF solution, 2mmol) at -78°C and was stirred for 1h. After 2,2-dimethylpropylidenebenzylamine 3c (0.18g, 1mmol) was added, the reaction mixture was warmed to room temperature and stirred for overnight. GC analysis of an aliquot showed the formation of 4c in 7% yield after hydrolysis. The reaction mixture was quenched with 20% NaHCO3 solution and extract with ether, dried over NaSO4. Filtration followed by concentration provided an oily compound. Column chromatography afford the desired compounds.
Stoichiometric reaction of imine 3c with 2 followed by addition of Grignard reagents
To a solution of Cp2ZrCl2 (0.29g, 1.0mmol) in THF (5ml) was added ethylmagnesium bromide (1.0M THF solution, 2mmol) at -78°C and was stirred for 1h. After 2,2-dimethylpropylidenebenzylamine 3c (0.18g, 1mmol) was added and the reaction mixture was warmed to room temperature for 30 min. MeMgBr (1 mmol) was added and the reaction mixture was stirred for 3h at room temperature. GC analysis showed the formation of 4c in 40% yield after hydrolysis. When MeMgBr (4 mmol) was added, under the same conditions, the product 4c was formed in 70% yield. Deuterolysis instead of hydrolysis of the reaction mixture after addition of 4 eq of MeMgBr afforded the deuterated product 4c DCH2CH2(tBu)CHNDCH2Ph with 65% D incorporation. The results of adding 1 equiv. or 4 equiv. of EtMgBr, n-BuMgCl, sec-BuMgCl, and t-BuMgCl are shown in Table 2.
Stoichiometric reaction of imine 3c with 2 followed by addition of Grignard reagents and CuCl: Formation of ethylated imine (7).
To a solution of Cp2ZrCl2 (0.35 g, 1.1 mmol) in THF (5 mL) was added EtMgBr (2.3 mL, 0.95 M, THF solution, 2.2 mmol) at -78°C. The mixture was stirred at -78°C for 1h. After 2,2-dimethylpropylidenebenzylamine 3c (0.18 g, 1.0 mmol) was added and the reaction mixture was warmed to room temperature for 30 min. Then, MeMgBr (4.0 mmol) was added and kept for 6h at the same temperature. To the reaction mixture was added CuCl (198 mg, 2.0 mmol) and kept for 6h at room temperature. The reaction mixture was quenched with (20%) NaHCO3 solution. The organic layer was extracted with hexane. The extract was washed with brine, and water and dried over MgSO4. The solvent was evaporated in vacuo to give a light yellow liquid which was purified by column chromatography (hexane : ether = 70 : 30) to give pure compound (7). A colorless liquid (48%): 1H NMR (CDCl3, Me4Si) d 0.73 (t, J = 6.6 Hz, 3H), 0.93 (s, 9H), 1.51-1.77 (m, 2H), 2.54-2.58 (dd, J = 1.65, 10.46 Hz, 1H), 7.39-7.77 (m, 5H), 8.15 (s, 1H); 13C NMR(CDCl3, Me4Si) d 1.84, 22.32, 27.03 (3C), 34.40, 82.92, 128.11 (2C), 128.46 (2C), 130.13, 136.59, 159.07. HRMS calcd for C14H21N 204.1752, found 204.1763.
Reaction of a mixture of imine 3a and 2 with allyl chloride in the presence of CuCl: Formation of (8a).
To a solution of Cp2ZrCl2 (0.35 g, 1.1 mmol) in THF (5 mL) was added EtMgBr (2.3 mL, 0.95 M, THF solution, 2.2 mmol) at -78°C. The mixture was stirred at -78°C for 1h. After benzylidenebenzylamine 3a (0.20 g, 1.0 mmol) was added and the reaction mixture was warmed to room temperature for 3h. To the reaction mixture was added allyl chloride ( 1.0 mmol) and CuCl (99.0 mg, 1.0 mmol) and kept at room temperature for 3h. The reaction mixture was quenched with (20%) NaHCO3 solution. The organic layer was extracted with hexane. The extract was washed with brine, and water and dried over MgSO4. The solvent was evaporated in vacuo to give a light yellow liquid which was purified by column chromatography (hexane : ether=70 : 30) to give pure compound (8a). A colorless liquid (48%) 1H NMR (CDCl3, Me4Si) d 1.21-1.39 (m, 2H), 1.59-1.74 (m, 2H), 1.98 (q, J = 7.2 Hz, 2H), 3.49-3.66 (m, 4H), 4.87-4.95 (m, 2H), 5.67-5.76 (m, 1H), 7.21-7.35 (m, 10H); 13C NMR(CDCl3, Me4Si) d 25.56, 33.67, 37.79, 51.48, 62.40, 114.55, 126.77, 126.92, 127.29 (2C), 128.119 (2C), 128.29 (2C), 128.34 (2C), 138.59, 140.66, 144.18. HRMS calcd for C19H23N 265.1830, found 265.1840.
Reaction of a mixture of imine 3a and 2 with propionyl chloride: Formation of (8b).
To a solution of Cp2ZrCl2 (0.35 g, 1.1 mmol) in THF (5 mL) was added EtMgBr (2.3 mL, 0.95 M, THF solution, 2.2 mmol) at -78°C. The mixture was stirred at -78°C for 1h. After benzylidenebenzylamine 3a (0.20 g, 1.0 mmol) was added and the reaction mixture was warmed to room temperature and kept at the same temperature for 3h. To the reaction mixture was added propionyl chloride (1.00 mmol) at 0°C for 1h. The reaction mixture was quenched with (20%) NaHCO3 solution. The organic layer was extracted with hexane. The extract was washed with brine, and water and dried over MgSO4. The solvent was evaporated in vacuo to give a light yellow liquid which was purified by column chromatography (hexane : ether = 70:30) to give pure compound (8b). A colorless liquid (57%). 1H NMR (CDCl3, Me4Si) d 0.90 (t, J = 7.3 Hz, 3H), 1.10 (t, J = 7.2 Hz, 3H), 1.85-1.92 (m, 1.5H), 2.13-2.31 (m, 1.5H), 2.62 (d, J = 6.7 Hz, 0.5H), 4.34 (q, J = 6.5 Hz, 1.5H), 5.91 (t, J = 7.7 Hz, 0.5H), 6.93 (d, J = 6.6 Hz, 1.5), 7.17-7.35 (m, 10H); 13C NMR(CDCl3, Me4Si) d 9.44, 11.30, 24.98, 27.11, 45.79, 58.10, 126.88 (2C), 127.52 (2C), 127.85, 128.01, 128.42 (2C), 128.61 (2C), 139.29, 139.52, 174.94. HRMS calcd for C19H23NO 218.1782, found 281.1780.
Reaction of a mixture of imine 3a and 2 with two equiv of propionyl chloride: Formation of (8c).
To a solution of Cp2ZrCl2 (0.35 g, 1.1 mmol) in THF (5 mL) was added EtMgBr (2.3 mL, 0.95 M, THF solution, 2.2 mmol) at -78°C. The mixture was stirred at -78°C for 1h. After benzylidenebenzylamine 3a䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䨂ffffff䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䨂ffffff䘀䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䨂ff䘀䘀䘀䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䨂ffffff䘀䘀䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䘀䘀䘀䠀䠀䠀䠀䘀䘀䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䨂ffffff䘀䘀䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䘀䘀䘀䠀䠀䠀䠀䘀䘀䘀䘀눘眛䘀䘀䘀䠀䠀䠀䘀䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䘀䘀䘀䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䘀䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䘀䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䘀䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䘀䘀䘀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䠀䘀䘀䘀䠀䠀䠀䘀䘀䘀䘀䘀䘀䘀䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䠂䠂䠂䠂䠂䨂䨂䨂ýﴀý䠂䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䨂䨂䠂䠂䨂䨂䨂ý䠂䠂䠂䠂䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䠂䠂䨂䨂䨂ýﴀý䠂䠂䠂䨂䨂䨂ý䠂䠂䠂䠂䠂䠂䠂䠂䠂䨂䨂䨂䠂䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䠂䨂䨂䨂ý䠂䠂䠂䠂䠂䠂䠂䠂䠂䨂䨂䨂ýﴀýﴀ䠂䠂䨂䨂䨂ýﴀﴀ䠂䠂䨂䨂䨂ýSupplementary Material (ESI) for Chemical Communications
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