Category: 51173-05-8

Electric Literature of 51173-05-8, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 51173-05-8, name is 5-Fluoro-2-hydroxypyridine, molecular formula is C5H4FNO, The compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

Compound 4-80 was dissolved in sulfuric acid (the larger amounts indicated above) at rt and then heated to 65 C. A preformed solution of fuming nitric acid and sulfuric acid (the smaller amount indicated above) was added dropwise. The temperature was kept between 65 C. and 80 C. (rxn is exothermic and although the bath is at 65 C., temperature goes higher, usually 75, sometimes 80 C.). After the addition was complete, the reaction mixture was heated at 65 C. for an additional hr. The reaction mixture was then cooled to rt and poured in a flask containing ice) (20 g of ice/gr compound, evolution of gas occurred). A solid precipitated out and it was collected by filtration (1HNM showed 4-80 and something else (discarded)). The aqueous layer was extracted with AcOEt several times (3-5) and concentrated on a rotary evaporator under vacuum to afford a solid that was triturated with ether to afford 5-80 as a bright yellow solid. A total of 117 g of desired product was collected in the first crop (27% yield from diazonium salt). A portion did not crystallize: this oil was triturated with MeOH and Et2O to afford 3.6 g of 5-80; another precipitation from the mother liquid afforded an additional 6.23 g of the desired product 5-80. Total: 117.0+3.6+6.23=126.83. 30.4%). Yield for 3 steps (decomposition of diazonium salt; deprotection and nitration). Analytical data from Notebook: 53877-115: 1HNMR(delta, MeOD): 8.56-8.27 (dd, J=7.5, 3.3 Hz, 1H), 8.01 (d, J=3.3 Hz, 1H); LC/MS(M+1)+=158.9; rt=0.15 min. Note: A portion of the aqueous acidic solution was taken and neutralized with Na2CO3 until effervescence stopped and then it was extracted with AcOEt A different product was obtained. No desired product in these extracts.

According to the analysis of related databases, 51173-05-8, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Ueda, Yasutsugu; Connolly, Timothy P.; Kadow, John F.; Meanwell, Nicholas A.; Wang, Tao; Chen, Chung-Pin H.; Yeung, Kap-Sun; Zhang, Zhongxing; Leahy, David Kenneth; Pack, Shawn K.; Soundararajan, Nachimuthu; Sirard, Pierre; Levesque, Kathia; Thoraval, Dominique; US2005/209246; (2005); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Electric Literature of 51173-05-8, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 51173-05-8, name is 5-Fluoro-2-hydroxypyridine, molecular formula is C5H4FNO, The compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

Compound 4-80 was dissolved in sulfuric acid (the larger amounts indicated above) at rt and then heated to 65 C. A preformed solution of fuming nitric acid and sulfuric acid (the smaller amount indicated above) was added dropwise. The temperature was kept between 65 C. and 80 C. (rxn is exothermic and although the bath is at 65 C., temperature goes higher, usually 75, sometimes 80 C.). After the addition was complete, the reaction mixture was heated at 65 C. for an additional hr. The reaction mixture was then cooled to rt and poured in a flask containing ice) (20 g of ice/gr compound, evolution of gas occurred). A solid precipitated out and it was collected by filtration (1HNM showed 4-80 and something else (discarded)). The aqueous layer was extracted with AcOEt several times (3-5) and concentrated on a rotary evaporator under vacuum to afford a solid that was triturated with ether to afford 5-80 as a bright yellow solid. A total of 117 g of desired product was collected in the first crop (27% yield from diazonium salt). A portion did not crystallize: this oil was triturated with MeOH and Et2O to afford 3.6 g of 5-80; another precipitation from the mother liquid afforded an additional 6.23 g of the desired product 5-80. Total: 117.0+3.6+6.23=126.83. 30.4%). Yield for 3 steps (decomposition of diazonium salt; deprotection and nitration). Analytical data from Notebook: 53877-115: 1HNMR(delta, MeOD): 8.56-8.27 (dd, J=7.5, 3.3 Hz, 1H), 8.01 (d, J=3.3 Hz, 1H); LC/MS(M+1)+=158.9; rt=0.15 min. Note: A portion of the aqueous acidic solution was taken and neutralized with Na2CO3 until effervescence stopped and then it was extracted with AcOEt A different product was obtained. No desired product in these extracts.

According to the analysis of related databases, 51173-05-8, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Ueda, Yasutsugu; Connolly, Timothy P.; Kadow, John F.; Meanwell, Nicholas A.; Wang, Tao; Chen, Chung-Pin H.; Yeung, Kap-Sun; Zhang, Zhongxing; Leahy, David Kenneth; Pack, Shawn K.; Soundararajan, Nachimuthu; Sirard, Pierre; Levesque, Kathia; Thoraval, Dominique; US2005/209246; (2005); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Electric Literature of 51173-05-8, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 51173-05-8, name is 5-Fluoro-2-hydroxypyridine, molecular formula is C5H4FNO, The compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

Compound 4-80 was dissolved in sulfuric acid (the larger amounts indicated above) at rt and then heated to 65 C. A preformed solution of fuming nitric acid and sulfuric acid (the smaller amount indicated above) was added dropwise. The temperature was kept between 65 C. and 80 C. (rxn is exothermic and although the bath is at 65 C., temperature goes higher, usually 75, sometimes 80 C.). After the addition was complete, the reaction mixture was heated at 65 C. for an additional hr. The reaction mixture was then cooled to rt and poured in a flask containing ice) (20 g of ice/gr compound, evolution of gas occurred). A solid precipitated out and it was collected by filtration (1HNM showed 4-80 and something else (discarded)). The aqueous layer was extracted with AcOEt several times (3-5) and concentrated on a rotary evaporator under vacuum to afford a solid that was triturated with ether to afford 5-80 as a bright yellow solid. A total of 117 g of desired product was collected in the first crop (27% yield from diazonium salt). A portion did not crystallize: this oil was triturated with MeOH and Et2O to afford 3.6 g of 5-80; another precipitation from the mother liquid afforded an additional 6.23 g of the desired product 5-80. Total: 117.0+3.6+6.23=126.83. 30.4%). Yield for 3 steps (decomposition of diazonium salt; deprotection and nitration). Analytical data from Notebook: 53877-115: 1HNMR(delta, MeOD): 8.56-8.27 (dd, J=7.5, 3.3 Hz, 1H), 8.01 (d, J=3.3 Hz, 1H); LC/MS(M+1)+=158.9; rt=0.15 min. Note: A portion of the aqueous acidic solution was taken and neutralized with Na2CO3 until effervescence stopped and then it was extracted with AcOEt A different product was obtained. No desired product in these extracts.

According to the analysis of related databases, 51173-05-8, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Ueda, Yasutsugu; Connolly, Timothy P.; Kadow, John F.; Meanwell, Nicholas A.; Wang, Tao; Chen, Chung-Pin H.; Yeung, Kap-Sun; Zhang, Zhongxing; Leahy, David Kenneth; Pack, Shawn K.; Soundararajan, Nachimuthu; Sirard, Pierre; Levesque, Kathia; Thoraval, Dominique; US2005/209246; (2005); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

With the rapid development and complex challenges of chemical substances, the synthesis of new drugs is usually one of the most effective ways to increase yield.51173-05-8, name is 5-Fluoro-2-hydroxypyridine, molecular formula is C5H4FNO, molecular weight is 113.09, as common compound, the synthetic route is as follows.COA of Formula: C5H4FNO

Intermediate 4,4-fluoro-7-bromo-6-azaindole, was prepared according to the following scheme: [CHEMMOL-00081] [0364] A) fuming HNO3, H2SO4; [0365] B) POBr3/DMF, 110 C.; [0366] C) vinylmagnesium bromide, THF, -78 C. -20 C. [0367] Intermediate 4 was isolated as a brownish solid. MS m/z: (M+H)+ calcd for C7H5BrFN2: 214.96; found 214.97. HPLC retention time: 1.28 minutes (column G).

At the same time, in my other blogs, there are other synthetic methods of this type of compound,51173-05-8, 5-Fluoro-2-hydroxypyridine, and friends who are interested can also refer to it.

Reference:
Patent; Kadow, John F.; Regueiro-Ren, Alicia; Xue, Qiufen May; US2004/6090; (2004); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Related Products of 51173-05-8, The major producers of chemicals have been the Europe, Japan and China. Due to the growing call for a cleaner, greener environment, people will have to find innovative ways to maintain their relevance. Here is a compound 51173-05-8, name is 5-Fluoro-2-hydroxypyridine. This compound has unique chemical properties. The synthetic route is as follows.

a) 5-Fluoro-3-nitropyridin-2-ol A mixture of concentrated sulphuric acid (1 mL) and fuming nitric acid (1 mL) was added dropwise to a stirred, cooled (ice-bath) mixture of 5-fluoropyridin-2-ol (1.20 g, 10.6 mmol) and concentrated sulphuric acid (2.7 mL). The mixture was warmed to ambient temperature and then to 85 C. After 2 hours, the mixture was cooled and poured onto ice-water. The precipitate was filtered and dried to give the title compound (0.72 g, 43%) as a yellow solid. LRMS (m/z): 157 (M-1)+. 1H NMR delta (300 MHz, DMSO-d6): 8.28 (s, 1H), 8.67 (s, 1H).

According to the analysis of related databases, 51173-05-8, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Almirall, S.A.; EP2527344; (2012); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem