- Extending motifs in lithiocuprate chemistry: Unexpected structural diversity in thiocyanate complexes
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The new area of lithio(thiocyanato)cuprates has been developed. Using inexpensive, stable and safe CuSCN for their preparation, these complexes revealed Lipshutz-type dimeric motifs with solvent-dependent point group identities; planar, boat-shaped and chair shaped conformers are seen in the solid state. In solution, both Lipshutz-type and Gilman structures are clearly seen. Since the advent in 2007 of directed ortho cupration, effort has gone into understanding the structure-reactivity effects of amide ligand variation in and alkali metal salt abstraction from Lipshutz-type cuprates such as (TMP)2Cu(CN)Li2(THF) 1 (TMP = 2,2,6,6-tetramethylpiperidide). The replacement of CN- with SCN- is investigated presently as a means of improving the safety of lithium cuprates. The synthesis and solid state structural characterization of reference cuprate (TMP)2Cu(CN)Li2(THP) 8 (THP = tetrahydropyran) precedes that of the thiocyanate series (TMP)2Cu(SCN)Li2(L) (L = OEt29, THF 10, THP 11). For each of 9-11, preformed TMPLi was combined with CuSCN (2 : 1) in the presence of sub-stoichiometric Lewis base (0.5 eq. wrt Li). The avoidance of Lewis basic solvents incurs formation of the unsolvated Gilman cuprate (TMP)2CuLi 12, whilst multidimensional NMR spectroscopy has evidenced the abstraction of LiSCN from 9-11 in hydrocarbon solution and the in situ formation of Gilman reagents. The synthetic utility of 10 is established in the selective deprotometalation of chloropyridine substrates, including effecting transition metal-free homocoupling in 51-69% yield.
- Peel, Andrew J.,Hedidi, Madani,Bentabed-Ababsa, Ghenia,Roisnel, Thierry,Mongin, Florence,Wheatley, Andrew E. H.
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- Efficient Phosphorus-Free Chlorination of Hydroxy Aza-Arenes and Their Application in One-Pot Pharmaceutical Synthesis
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The chlorination of hydroxy aza-arenes with bis(trichloromethyl) carbonate (BTC) and SOCl2 has been effectively performed by refluxing with 5 wt % 4-dimethylaminopyridine (DMAP) as a catalyst. Various substrates are chlorinated with high yields. The obtained chlorinated aza-arenes can be used directly with simple workup for succedent one-pot synthesis on a large scale.
- Wang, Jian,Li, Yan-Hui,Pan, Song-Cheng,Li, Ming-Fang,Du, Wenting,Yin, Hong,Li, Jing-Hua
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supporting information
p. 146 - 153
(2020/03/10)
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- Transition-metal-free decarboxylative halogenation of 2-picolinic acids with dihalomethane under oxygen conditions
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A convenient and efficient method for the synthesis of 2-halogen-substituted pyridines is described. The decarboxylative halogenation of 2-picolinic acids with dihalomethane proceeded smoothly via N-chlorocarbene intermediates to afford 2-halogen-substituted pyridines in satisfactory to excellent yields under transition-metal-free conditions. This new type of decarboxylative halogenation is operationally simple and exhibits high functional-group tolerance.
- Zhang, Xitao,Feng, Xiujuan,Zhang, Haixia,Yamamoto, Yoshinori,Bao, Ming
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supporting information
p. 5565 - 5570
(2019/10/22)
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- Preparation method of non-transition metal-catalyzed 2-halogenated pyridine compound
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The invention provides a preparation method of a non-transition metal-catalyzed 2-halogenated pyridine compound. The 2-halogenated pyridine compound is an important component of many medicines and bioactive molecules and has important application in the fields of organic synthesis, medicinal chemistry and the like and wide market prospects. The invention relates to the preparation method of the non-transition metal-catalyzed 2-halogenated pyridine compound. According to the method, pyridine-2-carboxylic acid, derivatives of the pyridine-2-carboxylic acid, NaF, KF, CsF, TBAF, NaCl, KCl, CsCl, TBAC, NCS, NaBr, KBr, CsBr, Br2, TBAB, NBS, NaI, KI, CsI, I2 and NIS are used as raw materials, and under the presence of base and an accelerant and mild conditions, the 2-halogenated pyridine compoundis synthesized. The method has the advantages that the steps are simple, the raw materials are easy to obtain, the reaction conditions are mild and the like; the method has great use value and socialand economic benefits.
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Paragraph 0048-0050
(2018/10/11)
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- PROCESS FOR MAKING 2-CHLORO-5-METHYLPYRIDINE
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Processes for the preparation of 2-chloro-5-methylpyridine are described.
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Paragraph 0056
(2017/01/31)
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- PROCESS FOR MAKING 2-CHLORO-5-METHYLPYRIDINE
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Processes for the preparation of 2-chloro-5-methylpyridine are described.
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Page/Page column 5
(2015/08/06)
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- Reaction of N-fluoropyridinium fluoride with isonitriles: A convenient route to picolinamides
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Reaction of N-fluoropyridinium fluoride generated in situ with a series of isonitriles led to the formation of the corresponding picolinamides in good yields. A similar reaction sequence for quinoline yielded the respective derivatives of 2-quinoline carboxylic acid. The proposed reaction mechanism involves the intermediate formation of a highly reactive carbene species.
- Kiselyov, Alexander S.
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p. 2279 - 2282
(2007/10/03)
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- Facile and Selective Synthesis of Chloromethylpyridines and Chloropyridines Using Diphosgene/Triphosgene
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Diphosgene and triphosgene in the presence of amines were found to be an excellent chlorinating agents with high selectivity for the preparation of chloromethylpyridines and chloropyridines from picoline-N-oxides and pyridine-N-oxides respectively.
- Narendar,Gangadasu,Ramesh, Ch.,Raju, B. China,Rao, V. Jayathirtha
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p. 1097 - 1103
(2007/10/03)
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- Process for the preparation of 2-halogeno-pyridine derivatives
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A process for the preparation of a 2-halogeno-pyridine of the formula STR1 in which X represents halogen and Y represents halogen, nitro, formyl, cyano, carboxyl, carbamoyl, alkyl, halogenoalkyl, alkoxyalkyl, dialkoxyalkyl, alkoxycarbonyl, alkylaminocarbonyl or dialkylaminocarbonyl, which comprises in a first stage reacting a pyridine 1-oxide of the formula STR2 with an organic nitrogen base A and an electrophilic compound, optionally in the presence of a diluent, to produce a compound of the formula STR3 in which A represents the radical of an organic nitrogen base, and Z- represents an anion formed from an electrophilic compound, optionally isolating and optionally purifying the compound of the formula (III).
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- Utilizing Acetyl Hypofluorite for Chlorination, Bromination, and Etherification of the Pyridine System
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Acetyl hypofluorite, which is easily made from F2, possesses a strong electrophilic fluorine.This electrophile is able to attach itself to the nitrogen atom of pyridine and activate the ring toward nucleophilic attacks.The ultimate elimination of HF results in an overall easy nucleophilic displacement of the hydrogen of the important 2-position .The nucleophiles used: Clδ-, Brδ-, ROδ-, originate from solvents such as CH2Cl2, CH2Br2, and various primary alcohols.Thus, 2-halo- or 2-alkoxypyridines were formed.The reaction conditions (room temperature, very short reaction times, and good yields) transform the task of direct substitution of the pyridine ring from an extremely difficult to a very easy procedure.
- Hebel, David,Rozen, Shlomo
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p. 6298 - 6301
(2007/10/02)
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- Le phenyl-lithium: nouvel agent de metallation du cycle pyridinique
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Nucleophilic addition was the sole reaction of phenyl-lithium with a pyridinic ring; now the novel catalysed metallation, with phenyl-lithium, of many substituted pyridine compounds giving various derivatives in high yields with many different reagents, has been achieved.
- Mallet, Marc
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- HALOGEN-SUBSTITUITED PYRIDINES. 3.* CYCLIZATION OF ADDUCTS OF α,α-DICHLOROPROPIONITRILE WITH ACRYLIC DERIVATIVES TO CHLOROPYRIDINES
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Reactions of α,α-dichloropropionitrile with acrylic derivatives in the presence of Cu2Cl2 gave a series of substituted 2,4-dichloro- and 2-chloro-5-oxoalkanonitriles.Their cyclization to chloropyridines has been studied.
- Shvekhgeimer, M.-G. A.,Kobrakov, K. I.,Sychev, S. S.,Promonenkov, V. K.
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p. 428 - 433
(2007/10/02)
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- Atypical Antipsychotic Agents: Patterns of Activity in a Series of 3-Substituted 2-Pyridinyl-1-piperazine Derivatives
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A series of 3-substituted 2-pyridinyl-1-piperazine derivaties have been appended to cyclic imide groups and evaluated for their potential antipsochotic activity.The dopamine receptor affinities of these target molecules, as well as their ability to block apomorphine-induced stereotypy or reverse neuroleptic-induced catalepsy, was dependent on the lipophilic and electronic characteristics of the substituent situated on the pyridine ring.Groups with +? and -? values were most consistent with the desired biological profile of the target molecules, the cyano moiety being the optimum choice.Evaluation of compound 12 in a monkey model of amphetamine psychosis, and the regional selectivity it expresses for the A10 dopaminergic cell bodies in electrophysiological experiments, suggest this compound would be an atypical antipsychotic agent with few side effects.
- New, James S.,Yevich, Joseph P.,Temple, Davis L.,New, Kimberly B.,Gross, Sharon M.,et al.
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p. 618 - 624
(2007/10/02)
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- ANTIPSYCHOTIC CYCLIC IMIDE DERIVATIVES OF 2-(4-BUTYLPIPERAZIN-1-YL) PYRIDINES, COMPOSITIONS AND USE
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Disubstituted N,N-piperazinyl derivatives are disclosed wherein one substituent is a substituted pyridin-2-yl ring and the second substituent is a butylene chain attached to cyclic imide heterocycles such as azaspiro 4.5!decanedione, dialkylglutarimide, thiazolidinedione, spirocyclopentylthiazolidinedione, or morpholine-2,6-dione. The compounds have psychotropic properties and 2-4-4-(2,4-dioxo-1-thia-3-azaspiro 4. 5!nonane-3-yl)butyl!-1-piperazinyl!-pyridine-3-carboxaldehyde is a typical embodiment having selective antipsychotic activity.
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- Site-Selectivity in the Reaction of 3-Substituted Pyridine 1-Oxides with Phosphoryl Chloride
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Site-selectivity in the reaction of 3-substituted pyridine 1-oxide with phosphoryl chloride was investigated.When a strongly electron-withdrawing group (e.g.CN, CONRR', COOR, or NO2) was substituted at the 3-position, the reaction of 3-substituted pyridine 1-oxides with phosphoryl chloride yielded 3-substituted 2-chloropyridines as the main products.Keywords- site-selectivity; 3-substituted pyridine 1-oxide; phosphoryl chloride; 3-substituted 2-chloropyridine; chlorination
- Yamanaka, Hiroshi,Araki, Tomio,Sakamoto, Takao
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p. 2244 - 2247
(2007/10/02)
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- ANTIPSYCHOTIC CYCLIC IMIDE DERIVATIVES OF 2-(4-BUTYLPIPERAZIN-1-YL)PYRIDINES, COMPOSITIONS AND USE
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Disubstituted N,N-piperazinyl derivatives are disclosed wherein one substituent is a substituted pyridin-2-yl ring and the second substituent is a butylene chain attached to cyclic imide heterocycles such as azaspiro 4.5!decanedione, dialkylglutarimide, thiazolidinedione, spirocyclopentylthiazolidinedione, or morpholine-2,6-dione. The compounds have psychotropic properties and 2-4-4-(2,4-dioxo-1-thia-3-azaspiro 4. 5!nonane-3-yl)butyl!-1-piperazinyl!pyridine-3-carboxaldehyde is a typical embodiment having selective antipsychotic activity.
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