Tag: M.W=100-200

These common heterocyclic compound, 42726-73-8, name is tert-Butyl methyl malonate, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Formula: C8H14O4

EXAMPLE 125 Diethyl 2,2-Difluoroglutarate (b) Diethyl 2-ketoglutarate (a, 10.06 g, 49.74 mmol), methylene chloride (150 ml), and water (0.5 ml) were combined in a stainless steel bomb under N2 and cooled to -78. Sulfur tetrafluoride (~90 g, 833 mmol) was condensed in a polypropylene bottle at -78 and added to the reaction mixture. The bomb was sealed, then allowed to come to room temperature. After a total of 20 hrs, the bomb was vented through aqueous sodium hydroxide. The reaction mixture was worked up with methylene chloride, washing with aqueous sodium bicarbonate and brine. It yielded 11.38 g of crude yellow oil containing a white solid material. The white solid was filtered off and the oil distilled under reduced pressure through a Vigreux column. (bp 82-95, 5 mm). Total yield 6.27 g (57%) of the title compound as a light yellow oil. Silica gel tlc: Rf 0.47 in EtOAc:Hexane 1:3,

The synthetic route of tert-Butyl methyl malonate has been constantly updated, and we look forward to future research findings.

Reference:
Patent; The University of Chicago; US4324730; (1982); A;,
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Some common heterocyclic compound, 42122-44-1, name is Methyl 3-(4-fluorophenyl)propiolate, molecular formula is C10H7FO2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Product Details of 42122-44-1

EXAMPLE 1 Intermediate A To a solution of methyl 4-(fluorophenyl)propynoate (J. Org. Chem. 1987, 52(16), 3662-8) (13 g, 73 mmol) in methanol (60 ml) was added water (60 ml) followed by methylhydrazine (4 ml, 77 mmol), the mixture was stirred for 6 hrs at 60 C. then left to stand overnight. The solid was filtered and washed with water then a minimum volume of methanol and dried overnight, affording 7.7 g of 5-(4-fluorophenyl)-1-methyl-1,2-dihydropyrazol-3-one (55%).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 42122-44-1, its application will become more common.

Reference:
Patent; Castro Pineiro, Jose Luis; Collins, Ian James; Harrison, Timothy; US2005/143369; (2005); A1;,
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6914-71-2, name is 1,1-Cyclopropanedicarboxylic acid dimethyl ester, belongs to esters-buliding-blocks compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows. Application In Synthesis of 1,1-Cyclopropanedicarboxylic acid dimethyl ester

Comparative Example 1; According to the same manner as that described in Example 3, the reaction did not proceed and (S)-tert-leucinol and dimethyl cyclopropanedicarboxylate, which are starting materials, were recovered except that lithium methoxide was not used in Example 3.

The synthetic route of 6914-71-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Sumitomo Chemical Company, Limited; EP1698617; (2006); A1;,
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Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 383-62-0, name is Ethyl 2-chloro-2,2-difluoroacetate, This compound has unique chemical properties. The synthetic route is as follows., Product Details of 383-62-0

Example 1Production of alpha-silyl difluoroacetic acid ester (1) According to the above-described scheme, magnesium (243 mg, 10.0 mmol), chlorotrimethylsilane (Me3SiCl; 2.17 g, 20.0 mmol) and DMF (15 mL) were put into a two-neck reaction tube under nitrogen atmosphere. Ethyl chlorodifluoroacetate (Compound 3; 793 mg, 624 muL, 5.0 mmol) was added thereto with the reaction container being cooled in water bath, and then the mixture was stirred at room temperature for 1.5 hours. The reaction mixture was extracted with diethyl ether and washed with water, and an organic layer was dried with anhydrous sodium sulfate. Diethyl ether was distilled away under reduced pressure, and by carrying out the production by silica gel column chromatography, difluorotrimethylsilanylacetic acid ethyl ester (Compound 3a) was obtained with a yield of 43%.Note that in other working examples, as difluorotrimethylsilanylacetic acid ethyl ester (Me3Si-CF2CO2Et; Compound 3a), the product obtained in this working example was used.The results of instrumental analysis of the product (Compound 3a) are shown below:1H-NMR (CDCl3, TMS) delta4.32 (2H, q, J=7.0 Hz), 1.35 (3H, t, J=7.0 Hz), 0.237 (9H, s) 19F-NMR (CDCl3, C6F6) delta38.5 (2F, s) Mass m/e: (m/z) (%) 181 (6), 153 (10), 125 (6), 103 (8), 77 (26), 73 (100)

According to the analysis of related databases, 383-62-0, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Amii, Hideki; Fujikawa, Kenichi; Fujioka, Yasutaka; Matsuura, Makoto; US2012/220795; (2012); A1;,
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Related Products of 379228-57-6, These common heterocyclic compound, 379228-57-6, name is Methyl 2-amino-4,6-difluorobenzoate, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

A stirred solution of compound 16b (2.70 g, 14.42 mmol) in i-PrOH (50 mL) was cooled to 0C and added with NCS (2.02 g, 15.15 mmol) in portions, the resulting yellow suspension was stirred at 0C to 30C for 12 h while monitoring with LCMS (turned to clean gradually). The reaction mixture was concentrated in vacuum directly to give the crude product, which was purified by flash column chromatography on silica gel (Condition: 65-75%B (A: 0.05%TFA in water; B: MeOH) ; Flow rate: 40 ml/min)) to give compound 16c (1000 mg purity 87.20%, and 500 mg starting material) as a white solid. LCMS: R t = 0.905 min in 5-95AB_1.5 min_220&254 chromatography (MERCK RP18e 25-2mm), MS (ESI) m/z= 189.9 [M-32] +. 1H NMR (400MHz, DMSO-d 6) delta 7.04 (br s, 2H), 6.61 (dd, J=1.8, 11.8 Hz, 1H), 3.82 (s, 3H).

The synthetic route of 379228-57-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; DIZAL (JIANGSU) PHARMACEUTICAL CO., LTD; LI, Zhengtao; ZOU, Hao; ZHU, Wei; SHEN, Changmao; WANG, Rumin; LIU, Wengeng; CHEN, Xiang; TSUI, Honchung; YANG, Zhenfan; ZHANG, Xiaolin; (307 pag.)WO2019/149164; (2019); A1;,
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Electric Literature of 454-31-9,Some common heterocyclic compound, 454-31-9, name is Ethyl 2,2-difluoroacetate, molecular formula is C4H6F2O2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

Step 2 Preparation of 4,4-difluoro-1-(3-fluoro-4-methoxyphenyl)-butane-1,3-dione Ethyl difluoroacetate (4.06 g, 32.7 mmol) was dissolved in methyl tert-butyl ether (50 mL). To the stirred solution was added 25 weight % sodium methoxide (7.07 g, 32.7 mmol) followed by 3′-fluoro-4′-methoxyacetophenone from Step 1 (5.0 g, 29.7 mmol). After stirring for 16 hours, 1N HCl (50 mL) was added. The organic layer was collected and washed with water (2*50 mL), dried over anhydrous MgSO4, filtered, and added to hexanes to precipitate a tan solid (7.0 g, 96%): mp 70-72 C.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Ethyl 2,2-difluoroacetate, its application will become more common.

Reference:
Patent; G. D. Searle & Co.; US6376528; (2002); B1;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Synthetic Route of 3618-04-0, The chemical industry reduces the impact on the environment during synthesis 3618-04-0, name is trans-Ethyl 4-hydroxycyclohexanecarboxylate, I believe this compound will play a more active role in future production and life.

tert-Butyldimethylchlorosilane (9.71 g, 64.45 mmol) was added portion wise to ethyl 4- hydroxycyclohexanecarboxylate (CAS no. 17159-80-7) (10 g, 58 mmol) and imidazole (7.9 g, 116 mmol) in DMF (58 mL) under nitrogen. The resulting solution was stirred at room temperature for 18 hours. The reaction mixture was diluted with diethyl ether (250 mL), and washed with saturated brine (500 mL). The organic layer was dried (MgSO4), filtered and evaporated to afford the product (16.3 g). This was used without any further purification.IH NMR (300 MHz, CDCl3) delta 0.02 – 0.07 (5H, m), 0.87 – 0.90 (9H, m), 0.92 (IH, s), 1.22 – 1.29 (3H, m), 1.30 – 1.54 (3H, m), 1.59 – 1.70 (2H, m), 1.87 – 2.04 (3H, m), 2.21 – 2.32 (IH, m), 3.70 – 3.89 (IH, m), 4.07 – 4.16 (2H, m).

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, trans-Ethyl 4-hydroxycyclohexanecarboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; WO2009/24821; (2009); A2;,
Ester – Wikipedia,
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Reference of 87-24-1, 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. 87-24-1 name is Ethyl 2-methylbenzoate, This 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 1-1 (1.97g, 12mmol, 1eq), NBS (2.35g, 13.2mmol, 1eq), AIBN (98.4mg, 0.6mmol, 0.05 eq) was dissolved in 20mL of acetonitrile, the reaction was heated at reflux overnight, with TCL plate detection reaction, after completion of the reaction, the solvent under reduced pressure to give the crude product spin dry, and separated by a silica gel column, particle size of 200-300 mesh silica gel, eluent ratio of methylene chloride / petroleum ether = 1: 1, yields 56%.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, Ethyl 2-methylbenzoate, and friends who are interested can also refer to it.

Reference:
Patent; University of Jinan; Lin, Weiying; Ren, Mingguang; Deng, Beibei; (14 pag.)CN105884713; (2016); A;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Application of 15568-85-1, In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 15568-85-1 as follows.

General procedure: 5-(Methoxymethylene)-2,2-dimethyl-1,3-dioxane-4,6-dione (0.5 g, 2.9 mmol) was added to a stirred solution of the 5-aminopyrazole 6 (2.9 mmol) in MeCN (10 mL). After stirring for 1 h, the solvent was removed in vacuo to complete the precipitation of the product.

According to the analysis of related databases, 15568-85-1, the application of this compound in the production field has become more and more popular.

Reference:
Article; Mackay, Martha; Nortcliffe, Andrew; McNab, Hamish; Hulme, Alison N.; Synthesis; vol. 47; 2; (2015); p. 242 – 248;,
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Synthetic Route of 73368-41-9, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 73368-41-9, name is Ethyl 4-amino-3-methoxybenzoate belongs to esters-buliding-blocks compound, it is a common compound, a new synthetic route is introduced below.

After adding acetonitrile (170 mL) and N-chlorosuccinimide (13.4 g, 100 mmol) to ethyl 4-amino-3-methoxybenzoate (17.8 g, 91.2 mmol) in that order, the mixture was stirred at 60 C. for 2 hours. The mixture was returned to room temperature, and the solvent in the mixture was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (mixture of n-heptane and ethyl acetate: n-heptane/ethyl acetate=8/1 then 4/1) to obtain the title compound (15.8 g, 68.8 mmol). 1H-NMR (CDCl3) delta: 1.37 (t, J=6.8 Hz, 3H), 3.91 (s, 3H), 4.32 (q, J=6.8 Hz, 2H), 4.58 (br.s, 2H), 7.36 (d, J=1.8 Hz, 1H), 7.65 (d, J=1.8 Hz, 1H).

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, Ethyl 4-amino-3-methoxybenzoate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Eisai R & D Management Co., Ltd.; US2009/259049; (2009); A1;,
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics