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Preparation method of mild diazomethane derivative

A technology for diazomethane and derivatives, applied in the field of preparation of diazomethane derivatives, can solve the problems of harsh conditions, limited practicability, unfavorable subsequent reactions, etc., and achieves stable chemical properties, simple synthesis operations, and cheap and easy raw materials. the effect

Active Publication Date: 2017-05-03
NORTHEAST NORMAL UNIVERSITY
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  • Abstract
  • Description
  • Claims
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Problems solved by technology

[0003] Diazo compounds are very active reaction intermediates, which also cause their inherent defects: toxicity and explosiveness, which bring difficulties to the synthesis and further utilization of diazo compounds
However, the conditions for the in situ generation of diazo compounds in the prior art are usually harsh, which is very unfavorable for subsequent reactions, making the practicability of diazo precursors in organic synthesis highly limited

Method used

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  • Preparation method of mild diazomethane derivative
  • Preparation method of mild diazomethane derivative
  • Preparation method of mild diazomethane derivative

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preparation example Construction

[0072] The invention provides a kind of preparation method of diazomethane derivative, comprising the following steps:

[0073] (1) Carry out substitution reaction with EWG substituted benzenesulfonyl chloride having the structure shown in formula I and hydrazine hydrate, obtain the EWG substituted benzenesulfonyl hydrazide having the structure shown in formula II;

[0074]

[0075] The EWG is an electron-withdrawing group; the electron-withdrawing group is 2-nitro, 4-nitro, 2,4-dinitro, 2-trifluoromethyl, 2-cyano, 2,3, One of 4,5,6-pentafluoro, 2,3,4,6-tetrafluoro, 2,4,6-trifluoro, 3,4,5-trifluoro;

[0076] (2) Condensing the EWG substituted benzenesulfonyl hydrazide with the structure shown in formula II obtained in the step (1) with the aldehyde or ketone with the structure shown in formula III to obtain the EWG substituted benzene with the structure shown in formula IV Sulfonylhydrazone;

[0077]

[0078] The R 1 is aryl, heteroaryl, alkyl, alkenyl or alkynyl; R ...

Embodiment 1

[0110] (1)

[0111] Under nitrogen, add o-nitrobenzenesulfonyl chloride (11.0g, 50mmol) and tetrahydrofuran (100mL) into a 250mL reaction flask, stir until dissolved, cool to 0°C in an ice-water bath, add hydrazine hydrate (6.1mL, 125mmol) dropwise , dropwise, react at 0°C until o-nitrobenzenesulfonyl chloride disappears as monitored by thin-layer chromatography, pour the reaction solution into ethyl acetate (200mL), separate the layers, wash the organic phase with 10% aqueous sodium chloride, dry, and extract Filter, drop in 800ml petroleum ether, have o-nitrobenzenesulfonyl hydrazide to separate out gradually, filter, recrystallize, vacuum-dry to obtain yellow solid (9.1g, yield 83.9%), i.e. o-nitrobenzenesulfonyl hydrazide, structure Characterized as figure 1 , figure 2 and the data shown below.

[0112] Yellow solid, m.p.100-101°C; 1 H-NMR (600MHz, CD 3 CN)δ8.10-8.08(m,1H),7.88-7.83(m,3H),6.96(s,1H),4.21(s,2H); 13 C-NMR (150MHz, CD 3 CN) δ149.6, 135.6, 133.5, 133.3...

Embodiment 2

[0121] (1) Under nitrogen, add o-trifluoromethylbenzenesulfonyl chloride (12.2g, 50mmol) and tetrahydrofuran (100mL) into a 250mL reaction flask, stir until dissolved, cool to -10°C, add hydrazine hydrate (6.1 mL, 125mmol). After dropping, react at -10°C until o-trifluoromethylbenzenesulfonyl chloride disappears as monitored by thin-layer chromatography, pour the reaction solution into ethyl acetate (200 mL), separate the layers, wash the organic phase with 10% aqueous sodium chloride solution, and dry. Suction filtration, drop in 800ml petroleum ether, have o-trifluoromethylbenzenesulfonyl hydrazide to separate out gradually, filter, recrystallize, vacuum-dry to obtain white crystal and be o-trifluoromethylbenzenesulfonyl hydrazide (9.7g, yield 80.7 %), its structure is characterized by Figure 7 , Figure 8 and the data shown below.

[0122] White crystals, m.p.111-112°C; 1 H-NMR (600MHz, CD 3 CN)δ8.20-8.19(m,1H),7.99-7.98(m,1H),7.86-7.83(m,2H),6.77(s,1H),3.87(s,2H); 1...

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Abstract

The invention discloses a preparation method of a mild diazomethane derivative. The preparation method comprises that EWG-substituted benzene sulfonyl chloride and hydrazine hydrate undergo a reaction to produce EWG-substituted benzene sulfonyl chloride, the EWG-substituted benzene sulfonyl chloride and aldehyde or ketone undergo a reaction to produce EWG-substituted benzenesulfonylhydrazone, and the EWG-substituted benzenesulfonylhydrazone, a base and an organic solvent are mixed and undergo a replacement reaction to produce a diazomethane derivative. The diazomethane derivative is not separated and purified and is further used for a tension small ring synthesis reaction and an insertion reaction. The benzene ring of benzenesulfonylhydrazone is introduced with an electron-withdrawing group EWG, and through electron effects and steric hindrance effects, the benzenesulfonyl group on the benzenesulfonylhydrazone is easily separated so that a diazomethane derivative is produced under very mild conditions and especially at the room temperature.

Description

technical field [0001] The invention relates to the field of synthesis of diazo compounds, in particular to a method for preparing mild diazomethane derivatives. Background technique [0002] Diazo compounds were discovered a century ago, but they are still one of the hotspots in the research of organic synthetic chemistry. Diazo compounds are a very important class of organic synthesis intermediates, which have a pivotal application value in the fields of organic synthetic chemistry, material chemistry, chemical biology, and new drug research and development. For example, under the induction of transition metals, the release of nitrogen gas from diazo compounds is the most popular standard method for the formation of metal carbenes, and has been widely used in various organic transformations. [0003] Diazo compounds are very active reaction intermediates, which also cause their inherent defects: toxicity and explosiveness, which bring difficulties to the synthesis and fur...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C07C2/88C07C13/28C07C245/14C07F7/08C07C17/263C07C25/18C07C245/18
CPCC07C2/88C07C17/263C07C245/14C07C245/18C07C303/38C07C2523/50C07C2531/025C07F7/0805C07F7/0827C07C311/49C07C13/28C07C25/18
Inventor 毕锡和刘兆洪杨旸李强强
Owner NORTHEAST NORMAL UNIVERSITY
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