光学活性化合物的工业合成

本文介绍了光学活性化合物研究现状及发展趋势。并从技术和经济角度论述了工业合成光学活性化合物的可能性     

具生物活性有机磷化合物的设计与合成

对氨基膦酸及磷肽的合成作了研究,同时考察了引入二氟次甲基及三氟甲基的方法。在此基础上研究成功基于[1,2]不对称诱导及[1,3]质子转移反应的手性合成方法。对多官能团的氨基膦酸及磷肽也作了研究。此外还制备了具1,1-双膦酸基的多种碳环化合物,对含磷酰基,特别对既含磷酰基又含三氟甲基的多种杂环化合物的合成方法与反应机理进行了报导。     

Chiral symmetric phosphoric acid esters as sources of optically active organophosphorus compounds

Chiral symmetric di- and trialkylphosphites, derivatives of (−)-borneol, (−)-menthol and (−)-1,2:5,6-di-O-isopropylidene-α-D-glucofuranose, were studied as starting reagents for the preparation of chiral organophosphorus compounds. The reaction occurs by asymmetric induction at the α-carbon atom of substituted α-alkylphosphonates. The stereoselectivity of the reaction depends on the structure of the starting compounds and the reaction conditions. The configuration of the alkylphosphonates was established by NMR spectroscopy, by transformation into α-hydroxyalkylphosphonic acids and by X-ray crystal structure analysis.     

Mild synthesis of organophosphorus compounds: reaction of phosphorus-containing carbenoids with organoboranes

Organoboranes react with phosphorus-containing carbenoids to produce a variety of functionalized organophosphorus compounds under mild conditions. In some cases, selective migration of one group attached to boron can be observed. Phosphonite-borane complexes are introduced as novel synthons for the synthesis of phosphinic esters.     

环链转移反应及其在合成杂环化合物中的应用

概括了环链转移反应的类型、机理,同时综述了环链转移反应在合成取代杂环化合物中的应用。     

Palladium-promoted asymetric oxyamination of alkenes application to the synthesis of optically active aryloxypropanolamines

Palladium-promoted oxyamination of some alkene using optically active N-methyl-α?enylethylamine as amine nucleophile, or using optically active N,N-dimethyl-α-phenylethylamine as ligand, produces optically active aminoalcohol derivatives in an optically yield of 3–60%. Oxyamination of aryl ethers gives optically active 1-amino-3-aryloxy-propan-2-ol derivatives, which are important β-blockers.     

Features of homolytic organophosphorus synthesis and its application

The features and selected applications of the homolytic organophosphorus synthesis based on the addition of phosphorous acid and its acid esters to unsaturated compounds, discovered by A.N. Pudovik in 1954.     

Modular synthesis of optically active lactones by Ru-catalyzed asymmetric allylic carboxylation and ring-closing metathesis reaction

A new synthetic route to optically active unsaturated γ- and δ-lactones has been demonstrated via asymmetric allylic carboxylation with a planar-chiral Cp'Ru catalyst and ring-closing metathesis reaction with a Grubbs II catalyst, and successfully applied to the enantioselective synthesis of (R)-(-)-massoialactone.     

Enantioselective synthesis of the optically active alpha-methylene-beta-hydroxy esters, equivalent compounds to Morita-Baylis-Hillman adducts, using successive asymmetric aldol reaction and oxidative deselenization

[Chemical reaction: See text] The asymmetric aldol reaction of a tetra-substituted ketene silyl acetal including an alkylseleno group with aldehydes has been developed by the promotion of Sn(OTf)2 coordinated with a chiral diamine to afford the corresponding aldols having chiral quaternary centers at the alpha-positions. The facile oxidative deselenization of these aldol compounds produces optically active alpha-methylene-beta-hydroxy esters which correspond to adducts prepared by the asymmetric Morita-Baylis-Hillman reaction.     

Preparation of peptides and active esters by a hydrolysis-dehydration reaction with phosphonites,and the application of the reaction to polymer synthesis

Dehydration reactions accompanied by hydrolysis of the condensation reagent itself, generalized as “hydrolysis-dehydration,” are seen in the formation of amides and esters using phosphites. The proposed concept was shown to be applicable also to the reactions with other phosphorus compounds, such as phosphinites, phosphonites and phosphonates. Aryl esters of these phosphorus compounds were effective for producing amides and esters, whereas alkyl esters were ineffective. Several peptides and active esters of amino acids were prepared using diphenyl phosphonites in the presence of tertiary amines and extended to the preparation of polypeptides and polyamides. Linear polypeptides and high molecular weight polyamides were obtained by means of diphenyl ethylphosphonite in N-methylpyrrolidone containing pyridine.     

The Grandberg reaction in the synthesis of biologically active compounds

The review is focused on the Grandberg synthesis, namely, the synthesis of tryptamines from arylhydrazines and γ-halocarbonyl compounds, as an exceptionally useful and efficient methodology to access biologically active indole heterocycles.     

Convenient synthesis of highly optically active 2,3,4,6-tetrasubstituted tetrahydropyrans via Prins cyclization reaction (PCR) of optically active homoallylic alcohols with aldehydes

Prins cyclization reaction (PCR) of optically active homoallylic alcohols, R^aC^*H(OH)CH₂CHCHCH₃ (1-substituted but-2-en-1-ol), with aldehydes (R^bCHO) in the presence of an acid-catalyst (HX) affords (2-R^b,3-CH₃,4-X,6-R^a)-tetrasubstituted tetrahydropyrans highly stereoselectively in good yields.     

A practical synthesis of optically active arylglycines via catalytic asymmetric Strecker reaction

A practical procedure for catalytic asymmetric synthesis of optically active arylglycine derivatives via optically active α-aminonitriles has been developed. The N-benzhydryl α-arylaminonitrile intermediates were prepared in excellent yield (89–99%) and enantiomeric purity (96 to >98% ee) by enantioselective cyanation of aldimines with TMSCN/ⁱPrOH in the presence of 2.5 mol % of an easily prepared Ti/chiral amino alcohol complex at 0 °C, without requiring slow addition of the cyanating agent. The easily racemized α-aminonitrile intermediates were efficiently hydrolyzed by an aqueous HCl/TFA mixture to give the arylglycine derivatives in good yield (60–92%) and moderate to excellent enantiomeric purity (85–98% ee).     

Efficient synthesis of optically active atropisomeric anilides through catalytic asymmetric N-arylation reaction

In the presence of (R)-DTBM-SEGPHOS-Pd(OAc)2 catalyst, N-arylation of ortho-tert-butyl-NH-anilides with 4-nitroiodobenzene proceeds with high enantioselectivity (89-95% ee) to give optically active atropisomeric anilides possessing N-C chiral axis. Furthermore, the intramolecular version of the present catalytic asymmetric N-arylation gave atropisomeric lactams with high optical purity (94-96% ee).     

Alkali metal polyphosphides as intermediates in the synthesis of organophosphorus compounds from elemental phosphorus

Russian Chemical Bulletin - Methods for the preparation of alkali metal polyphosphides, as well as their reactivity with respect to organic substrates, namely, electrophilic reagents and...     

Synthesis of optically active organoantimony compounds having an (S)-alpha-methylbenzyldimethylamine group and its evaluation for asymmetric reaction

Novel, enantiomerically pure organoantimony compounds having a C-chiral amine moiety, (S)-(alpha-methyl-2-di-p-tolylstibanobenzyl)dimethylamine [AMSb] (2) and its (eta(6)-arene)chromium complex [AMSb-Cr(CO)(3)] (4), were prepared from common (S)-(alpha-methylbenzyl)dimethylamine (1) via its ortho-lithiated intermediates in short steps. The catalytic activity and enantioselectivity of the ligands 2 and 4 for asymmetric reaction are evaluated, and the optically active (eta(6)-arene)chromium complex 4 has been shown to be an effective ligand for rhodium-catalyzed asymmetric hydrosilylation of ketones.     

Preparation of optically active α-hydroxy oxime ether by diastereoselective imino 1,2-Wittig rearrangement of hydroximates and its application to synthesis of (+)-cytoxazone

The diastereoselective imino 1,2-Wittig rearrangement of hydroximates provides a novel method for the construction of optically active α-hydroxy oxime ethers. Upon treatment with LDA, allyl p-methoxyphenylhydroximate carrying a chiral auxiliary smoothly underwent diastereoselective rearrangement to give the (R)-α-hydroxy oxime ether which was effectively converted into (+)-cytoxazone.