Synthese neuer 4-Hydroxybenzonitrilderivate und deren herbizide Eigenschaften

The synthesis of several new derivatives of 2-amino-4-hydroxybenzonitrile2 and their herbicidal screening data are described. Thus, halogenation and furtherSandmeyer-Reaction of2 leads to the 2,3,5-trihalogenated derivatives5 a–e. Reaction of ethyl chloroformate with the amino group of2 gives6 a, acylation7 a, b and8. The 3,5-dihalogenated compounds10 a–e are obtained from6 a and7 a, b by bromination or iodation. The hydroxyl group of6 a, 7 a, b and10 a, c, e reacts with N,N-disubstituted carbamyl chlorides to give6 c, d, 9 a, b, 11, 12 and13 a, b.

     

A mild and efficient method for halogenation of 3,5-dimethyl pyrazoles by ultrasound irradiation using N-halosuccinimides

The 4-halo-3,5-dimethyl pyrazoles have been synthetisized in good yields in short reaction times in the absence of a catalyst by reaction of 3,5-dimethyl pyrazoles with N-halosuccinimides (NBS, NCS and NIS) under ultrasound irradiation. Finally, the halogenation of pyrazoles with Br₂, ICl and I₂ was showed in similar conditions.     

The New Data for the Reaction of Arylenedioxy Trihalogenophosphoranes with Alkyl- and Arylacetylenes

The new data concerning the reaction between substituted arylenedioxy trihalogenophosphoranes and monoalkyl- or arylacetylenes are summarized. The reaction leads to formation of six-membered heterocycles-2-oxo-4-R-benzo[ e ]-1,2-oxaphosphorin-3-enes. The substituent effects in the phosphorane and acetylene molecules on the ipso -substitution and halogenation regiochemistry are discussed. The ipso -substitution of tert -butyl group on chlorine and the exchange of bromine on chlorine and iodine on hydrogen have been observed, along with formation of benzophosphorines. The interaction of tetrachloro- ortho -benzoquinone with phosphorus trichloride and arylacetylenes is proposed as a new modification of the reaction leading to the formation of benzo[ e ]-1,2-oxaphosphorines. The structures of some benzo[ e ]-1,2-oxaphosphorines are determined by the single crystal X-ray diffraction.     

Synthesis of Novel Bisphosphonate Inhibitors of Phosphoglycerate Kinase (3-PGK) (E.C.2.7.2.3)

Abstract

Novel, aromatic bisphosphonates have been synthesised as non-systematic analogues of 1,3-bisphosphoglyceric acid (1,3-BPG). These incorporate non-scissile α-halo and α-methylene phosphonates and have submicromolar K _i values for 3 -PGK.     

A new diphenylphosphinite ionic liquid (IL-OPPh2) as reagent and solvent for highly selective bromination, thiocyanation or isothiocyanation of alcohols and trimethylsilyl and tetrahydropyranyl ethers

A new diphenylphosphinite ionic liquid (IL-OPPh₂) is introduced. This ionic liquid is used as both a reagent and a solvent to convert alcohols and trimethylsilyl and tetrahydropyranyl (THP) ethers into their corresponding alkyl bromides, thiocyanates or isothiocyanates in the presence of Br₂ and SCN⁻ at 80 °C. In this ionic liquid, bromination and thiocyanation of alcohols occurs highly selectively in the presence of trimethylsilyl and THP-ethers and also between different classes of alcohols. The use of this ionic liquid allows easy separation of the desired products from the phosphinate by-product.     

Sieving properties of end group‐halogenated Pluronic polymer matrix in DNA separation under nondenaturing CE analysis

CE‐SSCP analysis is a well‐established DNA separation method that is based on variations in mobility caused by sequence‐induced differences in the conformation of single‐stranded DNA. The resolution of CE‐SSCP analysis was improved by using a Pluronic polymer matrix, and it has been successfully applied in various genetic analyses. Because the Pluronic polymer forms a micellar cubic structure in the capillary, it provides a stable internal structure for high‐resolution CE‐SSCP analysis. We hypothesized that formation of micellar cubic structure is influenced by the end hydroxyl group of the Pluronic polymer, which affords structural stability through hydrogen bonding. To test this hypothesis, the hydroxyl group was halogenated to eliminate the hydrogen bonding without disturbing the polarity of polymer matrix. CE‐SSCP resolution of two DNA fragments with a single base difference was significantly worse in the halogenated polymer matrices due to band broadening. The viscoelastic properties of control (which has hydroxyl group), chlorinated, and brominated F108 solution upon heating were also investigated by rheological experiments, and we found that gelation was significantly associated with resolution. In this series of experiments, the effect of the hydroxyl group in Pluronic polymer matrix on separation resolution of CE‐SSCP analysis was demonstrated.     

Preparation and reaction of bis (perfluoroalkanesulfonyl) methyl halides

Halogenation of the potassium or silver salts of bis(trifluoromethanesulfonyl)methane (CF3SO2)2CH2 and its cyclo analogues 1 with N-fluoro-bis(trifluoromethanesulfonyl)imine [(CF3SO2)2-NF], chlorine or bromine gave good yields of the corresponding α-halo disulfone (CF3SO2)2CHX and cyclo analogues 9, 10. The chemical transformation of these fluorinated α-halo-disulfones are described.     

Cyclization and halogenation of substituted o-allylphenols with diacetoxyiodobenzene in the presence of iodine or bromine

Substituted 2-halomethyl-2,3-dihydrobenzofurans were synthesized in one pot and in mild yield from substituted o-allylphenols with diacetoxyiodobenzene in the presence of 12 or Br2 in dry CH2Cl2 under reflux.     

Lewis acid-catalyzed one-pot sequential reaction for the synthesis of α-halogenated β-keto esters

A Lewis acid-catalyzed one-pot sequential transformation of β-keto esters, aromatic aldehydes, and NCS/NBS was reported. The reaction proceeds by way of Knoevenagel condensation/Nazarov cyclization/halogenation to give α-chloro- and α-bromo-β-keto esters in moderate yields with high diastereoselectivities. However, several aromatic aldehydes with electron-withdrawing substituents afforded unexpected α,β′-dichloro-β-keto esters in good to high yields.     

The regioselective C5 halogenation of quinolines using sodium halides under transition metal-free conditions

An efficient and mild halogenation of 8-acylaminoquinoline at the C5 position was described. The reaction utilized easily available sodium halides as the halogen sources and proceeded smoothly under transition metal-free conditions. Various 8-aminoquinolines with a number of functional groups were compatible in this reaction to afford the corresponding halogenated products in moderate to good yields. Moreover, the reaction conditions also tolerated the substrates without the 8-aminoquinolyl auxiliary, such as N-phenyl amide and N-naphthyl amide.