CN101514160B

CN101514160B - Method for preparing 2, 7-dibromo-4-nitrofluorenone

Info

Publication number: CN101514160B
Application number: CN2009100740908A
Authority: CN
Inventors: 张昭; 张鑫; 韩俊斌; 吉轩; 张鹏
Original assignee: Shanxi University
Current assignee: Shanxi University
Priority date: 2009-04-01
Filing date: 2009-04-01
Publication date: 2012-06-27
Anticipated expiration: 2029-04-01
Also published as: CN101514160A

Abstract

The invention provides a method for preparing 2, 7-dibromo-4-nitrofluorenone, comprising the followings steps: carrying out oxidation reaction on fluorene to obtain 9-fluorenone; carrying out bromination reaction on the 9-fluorenone to obtain 2, 7-dibromofluorenone; adding the 2, 7-dibromofluorenone and water into a reactor by the weight ratio of 1: 4-6; blending and heating the mixture; when the temperature is 80-90 DEG C, dripping the mixed acid of nitric acid and sulphuric acid rapidly; reacting for 3-5h under reflux, wherein the mol ratio of the 2, 7-dibromofluorenone to nitric acid and sulphuric acid is 1:70-80:60-70; adding water for quenching reaction; filtering; re-crystallizing the obtained solid with tetrahydrofuran and water, and drying the crystal to obtain the 2, 7-dibromo-4-nitrofluorenone. In the bromination and nitrification processes, water is used as solvent. The invention has moderate reaction conditions, simple operation, high total yield (83-88%), low cost, less environmental pollution and easy achievement of industrialization.

Description

2, the preparation method of 7-two bromo-4-nitryl fluorenones

Technical field

The present invention relates to aromatic organic compounds, specifically is a kind of 2, the preparation method of 7-two bromo-4-nitryl fluorenones.

Technical background

2,7-two bromo-4-nitryl fluorenones owing in the Fluorenone molecule, introduced the different functional group of a plurality of reactivity worth, therefore as important fine chemicals midbody, are widely used in the preparation of dyestuff, plastics, medicine and functional high molecule material etc.At present, relevant both at home and abroad report 2, the preparation method of 7-two bromo-4-nitryl fluorenones mainly is to be raw material with the fluorenes, bromo obtains 2; 7-dibromo fluorenes nitratedly again makes 2, and 7-two bromo-4-nitrofluorenes are at last through oxidation preparation 2; 7-two bromo-4-nitryl fluorenone (Tetrahedron, 2003,59,3131; Makromol.Chem., 1989,190,231-240; J.Med.Chem., 1965,8,491-497).Through method for preparing 2,7-two bromo-4-nitryl fluorenones, total recovery is low, cost is high, the reactants separate purification difficult, complicated operation, environmental pollution is big.

Summary of the invention

The object of the invention is to provide that a kind of reaction conditions is gentle, easy and simple to handle, productive rate is high, cost is low, it is little by 2 to pollute, the preparation method of 7-two bromo-4-nitryl fluorenones.

Provided by the invention 2, the preparation method of 7-two bromo-4-nitryl fluorenones comprises the steps:

(1) fluorenes is made the 9-Fluorenone through oxidizing reaction: be about to fluorenes and be dissolved in the THF, add Pottasium Hydroxide then, the weight ratio that feeds intake of fluorenes and THF is 1: 4-6; The molar ratio of fluorenes and Pottasium Hydroxide is 1: 0.5-1.5, stir atmospheric oxidation under room temperature, condition of normal pressure; Reacted suction filtration, distillation 6-8 hour; Washing, drying makes the 9-Fluorenone;

(2) the 9-Fluorenone is made 2 through bromo-reaction; The 7-dibromo fluorenone: be about to 9-Fluorenone and water by weight 1: 8-10 joins in the reactor drum, stirs heating;, temperature begins dripping bromine when rising to 75 ℃; The add-on of bromine is calculated in molar ratio as the 9-Fluorenone: bromine=1: 3.0-3.5, bromine divide three addings: add the 45%-50% of the total consumption of bromine for the first time, regulation system pH value is to neutral behind the back flow reaction 3-5h; The 25%-35% that adds for the second time the total consumption of bromine, regulation system pH value is to neutral behind the back flow reaction 4-6h; The 20%-25% that adds the total consumption of bromine for the third time, back flow reaction 4-6h adds the shrend reaction of going out, excessive bromine absorbs with saturated sodium sulfite solution, suction filtration is used water washing, drying, pure 2, the 7-dibromo fluorenone;

(3) with 2; 7-dibromo fluorenone and water are by weight 1: 4-6 joins in the reactor drum, stirs heating;, temperature begins to drip rapidly nitric acid and vitriolic mixing acid when rising to 80-90 ℃; The reaction 3-5h down that refluxes, wherein 2,7-dibromo fluorenone and nitric acid and vitriolic mol ratio are 1: 70-80: 60-70; Add the shrend reaction of going out, suction filtration, gained solid be with THF and water recrystallization, and be dry pure 2, the pure article of 7-two bromo-4-nitryl fluorenones, and productive rate is greater than 83%, and purity is greater than 98%.

The mass concentration of said nitric acid is 80-90%, and the vitriolic mass concentration is 90-98%.

Compared with prior art; The present invention is raw material with the fluorenes; Through oxidation, bromo, nitration reaction preparation 2,7-two bromo-4-nitryl fluorenones, wherein bromo and nitrifying process are as solvent with water; Reaction conditions is gentle, easy and simple to handle, overall yield high (83-88%), cost is low, environmental pollution is little, is easy to realize industriallization.

Embodiment

Reagent: fluorenes, CP; Pottasium Hydroxide, CP; THF, technical grade; Bromine, technical grade; Ethanol, CP; Concentrated nitric acid (85%), technical grade (by the preparation of 96% nitrosonitric acid); The vitriol oil (96-98%), technical grade.

Embodiment 1

Operation steps:, the 10L three-necked flask of mechanical stirrer and reflux condensing tube adds 1.66Kg fluorenes (10mol) in being housed, the 7L THF, 0.56Kg Pottasium Hydroxide (10mol) is opened and is stirred, and reaction is 10 hours under the room temperature.The reaction solution suction filtration is removed Pottasium Hydroxide, filtrating through distillation remove desolvate after the gained solid with water washing three times, dry must 9-Fluorenone 1.75Kg, productive rate 97.2%, purity is greater than 98.0%.

Be equipped with mechanical stirrer, reflux condensate device, TM and constant pressure funnel the 50L enamel reaction still add 1.75Kg (9.72mol) 9-Fluorenone and 15L water; Open and stir; Heating begins slowly to drip 2.45Kg (15.30mol) bromine, back flow reaction 3h with constant pressure funnel when temperature rises to 80 ℃; Be cooled to room temperature, regulation system pH value is to neutral.Heating continues to drip 2.02Kg (11.20mol) bromine with constant pressure funnel when temperature rises to 80 ℃, and back flow reaction 4h is cooled to room temperature, and regulation system pH value is to neutral.Heating drips 1.25Kg (6.95mol) bromine again when temperature rises to 80 ℃, back flow reaction 5h is cooled to room temperature, and regulation system pH value is to neutral.Suction filtration, products therefrom washs with clear water, and is dry pure 2,7-dibromo fluorenone 3.23Kg, productive rate 98.3%, purity is greater than 98.0%.

Add 3.23Kg (9.56mol) 2 at the 100L enamel reaction still that mechanical stirrer, reflux condensate device, TM and constant pressure funnel are housed, 7-dibromo fluorenone and 13L water are opened and are stirred; The oil bath heating when treating that temperature rises to 80 ℃, drips 34.27L concentrated nitric acid (85% rapidly; 678.76mol) and the 32.46L vitriol oil (96%; 583.16mol), about 25min drips, back flow reaction 3.5h; Stop heating, be cooled to room temperature, add the 20L shrend reaction of going out; Suction filtration is used water washing, drying, the yellow solid crude product, crude product is with THF and water recrystallization, dry must pure article 2,7-two bromo-4-nitryl fluorenone 3.28Kg, productive rate 89.6%, purity is greater than 98%.

Three-step reaction overall yield 85.6%.

Embodiment 22, the preparation of 7-two bromo-4-nitryl fluorenones

Operation steps:, the 10L three-necked flask of mechanical stirrer and reflux condensing tube adds 1.66Kg fluorenes (10mol) in being housed, the 7L THF, 0.42Kg Pottasium Hydroxide (7.5mol) is opened and is stirred, and reaction is 10 hours under the room temperature.The reaction solution suction filtration is removed Pottasium Hydroxide, filtrating through distillation remove desolvate after the gained solid with water washing three times, dry must 9-Fluorenone 1.74Kg, productive rate 96.7%, purity is greater than 98.0%.

Be equipped with mechanical stirrer, reflux condensate device, TM and constant pressure funnel the 50L enamel reaction still add 1.74Kg (9.67mol) 9-Fluorenone and 15L water; Open and stir; Heating begins slowly to drip 2.43Kg (15.18mol) bromine, back flow reaction 4h with constant pressure funnel when temperature rises to 80 ℃; Be cooled to room temperature, regulation system pH value is to neutral.Heating continues to drip 1.64Kg (10.25mol) bromine with constant pressure funnel when temperature rises to 80 ℃, and back flow reaction 5h is cooled to room temperature, and regulation system pH value is to neutral.Heating drips 1.20Kg (7.52mol) bromine again when temperature rises to 80 ℃, back flow reaction 5h is cooled to room temperature, and regulation system pH value is to neutral.Suction filtration, products therefrom washs with clear water, and is dry pure 2,7-dibromo fluorenone 3.19Kg, productive rate 97.6%, purity is greater than 98.0%.

Add 3.19Kg (9.44mol) 2 at the 100L enamel reaction still that mechanical stirrer, reflux condensate device, TM and constant pressure funnel are housed, 7-dibromo fluorenone and 13L water are opened and are stirred; The oil bath heating when treating that temperature rises to 80 ℃, drips 33.84L concentrated nitric acid (85% rapidly; 670.24mol) and the 32.05L vitriol oil (96%; 575.84mol), about 25min drips, back flow reaction 3.5h; Stop heating, be cooled to room temperature, add the 20L shrend reaction of going out; Suction filtration is used water washing, drying, the yellow solid crude product, crude product is with THF and water recrystallization, dry must pure article 2,7-two bromo-4-nitryl fluorenone 3.18Kg, productive rate 88.1%, purity is greater than 98%.

Three-step reaction overall yield 83.1%.

The physical constant of product and spectral data:

Product appearance: yellow solid; Fusing point: 194-196 ℃ .IR (KBr) cm ^-1: 3118.7,3078.2,1726.2,1612.4,1589.2,1529.5,1357.8,1433.0,1402.1,1357.8,1232.4,898.8,839.0,781.8,767.6,700.1. ¹HNMR δ 8.24 (d, J=1.8Hz, 1H), 8.06 (d, J=1.8Hz, 1H), 7.95 (d, J=8.3Hz, 1H), 7.91 (d, J=2.0Hz, 1H), 7.74 (d, J=8.3Hz, 2.0Hz, 1H). ¹³C NMR (75.5MHz, CDCl ₃): δ 190.3,149.4,141.9,139.2,137.1,134.8,131.7,128.2,125.8,125.4,123.5,119.7.

Claims

1. one kind 2, the preparation method of 7-two bromo-4-nitryl fluorenones comprises the steps:

(1) fluorenes is made the 9-Fluorenone through oxidizing reaction;

(2) the 9-Fluorenone is made 2 through bromo-reaction, the 7-dibromo fluorenone;

(3) with 2; 7-dibromo fluorenone and water are by weight 1: 4-6 joins in the reactor drum, stirs heating;, temperature begins to drip rapidly nitric acid and vitriolic mixing acid when rising to 80-90 ℃; The reaction 3-5h down that refluxes, wherein 2,7-dibromo fluorenone and nitric acid and vitriolic mol ratio are 1: 70-80: 60-70; Add the shrend reaction of going out, suction filtration, gained solid be with THF and water recrystallization, and be dry pure 2,7-two bromo-4-nitryl fluorenones.

2. as claimed in claim 1 a kind of 2, the preparation method of 7-two bromo-4-nitryl fluorenones, the mass concentration of described nitric acid is 80-90%, the vitriolic mass concentration is 90-98%.