Beta-diimide monovalent magnesium compound, preparation method thereof and application of beta-diimide monovalent magnesium compound in hydroboration of aldehyde or ketone

Abstract

The invention discloses a beta-diimide monovalent magnesium compound, a preparation method thereof and an application of the beta-diimide monovalent magnesium compound in hydroboration of aldehyde orketone. The preparation method comprises the following steps: under anhydrous and anaerobic conditions, a beta-diimine ligand reacts with a Grignard reagent, iodide of magnesium is generated and reduced by sodium, and a yellow crystal is obtained and is the beta-diimide monovalent magnesium compound. The beta-diimide monovalent magnesium compound is simple to synthesize, convenient to separate andpurify, clear in structure and high in yield; activity of the compound as a catalyst in catalysis of a reaction of aldehyde or ketone with pinacolborane is high, and the substrate universality is broad.

Description

technical field

[0001] The invention relates to the technical field of preparation of metal-organic compounds, in particular to a β-diimine monovalent magnesium compound, a preparation method thereof and an application in hydroboration of aldehydes and ketones. Background technique

[0002] It is well known that hydroboration is a very important reaction in catalytic reactions [Chong C.C., Kinjo R.ACSCatal.2015,5,3238; Geier S.J., Vogels C.M., Westcott S.A.ACS Symp.Ser.2016,1236,209.]. Although traditional transition metal catalysts have certain reactivity, they are relatively expensive, so it is imperative to replace traditional noble metal catalysts with other cheap catalysts [Vasilenko V., Blasius C.K., Wadepohl H., Gade L.H., Angew.Chem.Int . Ed. 2017, 56, 8393; Arévalo R., Vogels C.M., MacNeil G.A., Riera L., Péreza J., Westcott S.A. Dalton Trans. 2017, 46, 7750.]. Main group metals show obvious advantages because of their cheapness and environmental protection [Hill M...

Examples

Embodiment 1

[0024] The preparation of the iodide of β-diimine magnesium, the process is as follows:

[0025] In the absence of water and oxygen, 3.27 mmol of β-diimine ligand was dissolved in 25 mL of ether solution in a single-port reaction tube, and 3.92 mmol of methylmagnesium iodide was added dropwise to the above solution at -80°C, and reacted at room temperature for 24 hours. After filtration, the solid was sucked dry, and the filtrate was concentrated to 5 mL to obtain colorless crystals. The mass of solid and crystals was 1.63 g, and the yield was 94%. M.p. 271-273°C. NMR spectrum: 1 HNMR (600MHz, C 6 D. 6 ):δ6.99-6.91(m,6H,Ar-H),4.88(s,1H,CH),3.12(s,4H,OCH 2 CH 3 ),2.65(s,6H,CH 3 ),2.08(s,6H,CH 3 ),1.55(s,6H,NCCH 3 ),0.48(s,6H,OCH 2 CH 3 ) ppm. 13 C{ 1 H}NMR (151MHz,C 6 D. 6 ):δ168.87 (NCCH 3 ), 147.75, 131.57, 129.56, 124.76 (Ar-C), 95.31 (=CH), 65.96 (OCH 2 CH 3 ),23.52(OCH 2 CH 3 ), 21.09 (NCCH 3 ), 18.89, 13.15 (CH 3 ) ppm.

Embodiment 2

[0027] The preparation of the iodide of β-diimine magnesium, the process is as follows:

[0028] In the absence of water and oxygen, 3.27mmol of β-diimine ligand was dissolved in 25mL ether solution in a single-port reaction tube, and 3.60mmol of methylmagnesium iodide was added dropwise to the above solution at -60°C, and reacted at room temperature for 15h. After filtration, the solid was sucked dry, and the filtrate was concentrated to 5 mL to obtain colorless crystals. The mass of solid and crystals was 1.61 g, and the yield was 92%. M.p. 271-273°C. NMR spectrum: 1 HNMR (600MHz, C 6 D. 6 ):δ6.99-6.91(m,6H,Ar-H),4.88(s,1H,CH),3.12(s,4H,OCH 2 CH 3 ),2.65(s,6H,CH 3 ),2.08(s,6H,CH 3),1.55(s,6H,NCCH 3 ),0.48(s,6H,OCH 2 CH 3 ) ppm. 13 C{ 1 H}NMR (151MHz, C 6 D. 6 ):δ168.87 (NCCH 3 ), 147.75, 131.57, 129.56, 124.76 (Ar-C), 95.31 (=CH), 65.96 (OCH 2 CH 3 ),23.52(OCH 2 CH 3 ), 21.09 (NCCH 3 ), 18.89, 13.15 (CH 3 ) ppm.

Embodiment 3

[0030] The preparation of the iodide of β-diimine magnesium, the process is as follows:

[0031] In the absence of water and oxygen, 3.27 mmol of β-diimine ligand was dissolved in 25 mL of ether solution in a single-port reaction tube, and 3.27 mmol of methylmagnesium iodide was added dropwise to the above solution at -40°C, and reacted at room temperature for 15 h. After filtration, the solid was sucked dry, and the filtrate was concentrated to 5 mL to obtain colorless crystals. The mass of solid and crystals was 1.63 g, and the yield was 94%. M.p. 271-273°C. NMR spectrum: 1 HNMR (600MHz, C 6 D. 6 ):δ6.99-6.91(m,6H,Ar-H),4.88(s,1H,CH),3.12(s,4H,OCH 2 CH 3 ),2.65(s,6H,CH 3 ),2.08(s,6H,CH 3 ),1.55(s,6H,NCCH 3 ),0.48(s,6H,OCH 2 CH 3 ) ppm. 13 C{ 1 H}NMR (151MHz,C 6 D. 6 ):δ168.87 (NCCH 3 ), 147.75, 131.57, 129.56, 124.76 (Ar-C), 95.31 (=CH), 65.96 (OCH 2 CH 3 ),23.52(OCH 2 CH 3 ), 21.09 (NCCH 3 ), 18.89, 13.15 (CH 3 ) ppm.

technical field

[0001] The invention relates to the technical field of preparation of metal-organic compounds, in particular to a β-diimine monovalent magnesium compound, a preparation method thereof and an application in hydroboration of aldehydes and ketones. Background technique

[0002] It is well known that hydroboration is a very important reaction in catalytic reactions [Chong C.C., Kinjo R.ACSCatal.2015,5,3238; Geier S.J., Vogels C.M., Westcott S.A.ACS Symp.Ser.2016,1236,209.]. Although traditional transition metal catalysts have certain reactivity, they are relatively expensive, so it is imperative to replace traditional noble metal catalysts with other cheap catalysts [Vasilenko V., Blasius C.K., Wadepohl H., Gade L.H., Angew.Chem.Int . Ed. 2017, 56, 8393; Arévalo R., Vogels C.M., MacNeil G.A., Riera L., Péreza J., Westcott S.A. Dalton Trans. 2017, 46, 7750.]. Main group metals show obvious advantages because of their cheapness and environmental protection [Hill M...

Examples

Embodiment 1

[0024] The preparation of the iodide of β-diimine magnesium, the process is as follows:

[0025] In the absence of water and oxygen, 3.27 mmol of β-diimine ligand was dissolved in 25 mL of ether solution in a single-port reaction tube, and 3.92 mmol of methylmagnesium iodide was added dropwise to the above solution at -80°C, and reacted at room temperature for 24 hours. After filtration, the solid was sucked dry, and the filtrate was concentrated to 5 mL to obtain colorless crystals. The mass of solid and crystals was 1.63 g, and the yield was 94%. M.p. 271-273°C. NMR spectrum: 1 HNMR (600MHz, C 6 D. 6 ):δ6.99-6.91(m,6H,Ar-H),4.88(s,1H,CH),3.12(s,4H,OCH 2 CH 3 ),2.65(s,6H,CH 3 ),2.08(s,6H,CH 3 ),1.55(s,6H,NCCH 3 ),0.48(s,6H,OCH 2 CH 3 ) ppm. 13 C{ 1 H}NMR (151MHz,C 6 D. 6 ):δ168.87 (NCCH 3 ), 147.75, 131.57, 129.56, 124.76 (Ar-C), 95.31 (=CH), 65.96 (OCH 2 CH 3 ),23.52(OCH 2 CH 3 ), 21.09 (NCCH 3 ), 18.89, 13.15 (CH 3 ) ppm.

Embodiment 2

[0027] The preparation of the iodide of β-diimine magnesium, the process is as follows:

[0028] In the absence of water and oxygen, 3.27mmol of β-diimine ligand was dissolved in 25mL ether solution in a single-port reaction tube, and 3.60mmol of methylmagnesium iodide was added dropwise to the above solution at -60°C, and reacted at room temperature for 15h. After filtration, the solid was sucked dry, and the filtrate was concentrated to 5 mL to obtain colorless crystals. The mass of solid and crystals was 1.61 g, and the yield was 92%. M.p. 271-273°C. NMR spectrum: 1 HNMR (600MHz, C 6 D. 6 ):δ6.99-6.91(m,6H,Ar-H),4.88(s,1H,CH),3.12(s,4H,OCH 2 CH 3 ),2.65(s,6H,CH 3 ),2.08(s,6H,CH 3),1.55(s,6H,NCCH 3 ),0.48(s,6H,OCH 2 CH 3 ) ppm. 13 C{ 1 H}NMR (151MHz, C 6 D. 6 ):δ168.87 (NCCH 3 ), 147.75, 131.57, 129.56, 124.76 (Ar-C), 95.31 (=CH), 65.96 (OCH 2 CH 3 ),23.52(OCH 2 CH 3 ), 21.09 (NCCH 3 ), 18.89, 13.15 (CH 3 ) ppm.

Embodiment 3

[0030] The preparation of the iodide of β-diimine magnesium, the process is as follows:

[0031] In the absence of water and oxygen, 3.27 mmol of β-diimine ligand was dissolved in 25 mL of ether solution in a single-port reaction tube, and 3.27 mmol of methylmagnesium iodide was added dropwise to the above solution at -40°C, and reacted at room temperature for 15 h. After filtration, the solid was sucked dry, and the filtrate was concentrated to 5 mL to obtain colorless crystals. The mass of solid and crystals was 1.63 g, and the yield was 94%. M.p. 271-273°C. NMR spectrum: 1 HNMR (600MHz, C 6 D. 6 ):δ6.99-6.91(m,6H,Ar-H),4.88(s,1H,CH),3.12(s,4H,OCH 2 CH 3 ),2.65(s,6H,CH 3 ),2.08(s,6H,CH 3 ),1.55(s,6H,NCCH 3 ),0.48(s,6H,OCH 2 CH 3 ) ppm. 13 C{ 1 H}NMR (151MHz,C 6 D. 6 ):δ168.87 (NCCH 3 ), 147.75, 131.57, 129.56, 124.76 (Ar-C), 95.31 (=CH), 65.96 (OCH 2 CH 3 ),23.52(OCH 2 CH 3 ), 21.09 (NCCH 3 ), 18.89, 13.15 (CH 3 ) ppm.

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