Β-amino Alcohols Research Articles

Organocatalytic Enantioselective Acyloin Rearrangement of α‐Hydroxy Acetals to α‐Alkoxy Ketones

We report an unprecedented organocatalytic enantioselective acyloin rearrangement of α,α-disubstituted α-hydroxy acetals. In the presence of a catalytic amount of chiral binol-derived N-triflyl phosphoramide, α-hydroxy acetals rearranged to α-alkoxy ketones in good to high yields with high enantioselectivities. Formation of an ion pair between the in situ generated oxocarbenium ion and the chiral phosphoramide anion was proposed to be responsible for the highly efficient transfer of chirality. Conditions for removal of cyclohexyl and cyclopentyl groups from the corresponding α-alkoxy ketones were uncovered underpinning their potential general utility as hydroxy protecting groups. Conversion of the rearranged products to the enantioenriched α-hydroxy ketone, 1,2-diol, β-amino alcohol and 1,4-dioxane was also documented.

Zirconium triflate grafted on SBA-15 as a highly efficient solid acid catalyst for ring opening of epoxides by amines and alcohols

Metal (Al, Ti, Zr) triflate grafted mesoporous SBA-15 (AlTf/S, TiTf/S, ZrTf/S) samples were synthesized as inexpensive solid acid materials by a simple one-pot-two-step synthesis methodology. These materials were characterized by X-ray diffraction, N2-sorption, thermogravimetric analysis, Fourier transform infrared spectroscopy (FT-IR), in-situ pyridine FT-IR spectroscopy, and elemental analysis. ZrTf/S was found to be a highly efficient and reusable solid acid catalyst for ring opening of epoxides with amines and alcohols and produced β-amino alcohols and β-alkoxy alcohols respectively under ambient reaction conditions. The ZrTf/S catalyst showed the highest activity, which was attributed to its high acidity compared with that of the Ti and Al containing samples.

A simple method for the synthesis of 1,3-diaminopropan-2-ols derivatives and their ex vivo relaxant activity on isolated rat tracheal rings

A mild and eco-friendly method has been developed for the synthesis of a series of 1,3-diaminopropan-2-ols 8a–n. The epoxide of epichlorohydrin undergoes ring-opening with amines using MgSO4 or mixed metal oxides catalysts under mild and neutral conditions to afford the corresponding β-amino alcohols in excellent yields. Preliminary evaluation of relaxant activity of 8b–n was carried out on rat tracheal rings contracted by carbachol 1 μM. Most of the tested compounds exhibited significantly relaxant effects in a concentration-dependent manner. Compound 8n was found to be the most active, being twofolds more potent than theophylline (positive control). This compound has the potential for development as an anti-asthma drug.

Corrigendum: Acid‐Functionalized Mesoporous SBA‐15 as an Efficient Heterogeneous Organocatalyst for the Green Synthesis of β‐Amino Alcohol Derivatives

ChemistrySelectVolume 2, Issue 8 p. 2588-2588 CorrigendumFree Access Corrigendum: Acid-Functionalized Mesoporous SBA-15 as an Efficient Heterogeneous Organocatalyst for the Green Synthesis of β-Amino Alcohol Derivatives This article corrects the following: Acid-Functionalized Mesoporous SBA-15 as an Efficient Heterogeneous Organocatalyst for the Green Synthesis of β-Amino Alcohol Derivatives Swarbhanu Ghosh, Piyali Bhanja, Rostam Ali Molla, Resmin Khatun, Sk. Manirul Islam, Volume 2Issue 6ChemistrySelect pages: 2159-2165 First Published online: February 27, 2017 Swarbhanu Ghosh, Swarbhanu GhoshSearch for more papers by this authorPiyali Bhanja, Piyali Bhanja +91-33-2473-4971 | Fax: +91-33-2473-2805 Search for more papers by this authorRostam Ali Molla, Rostam Ali MollaSearch for more papers by this authorResmin Khatun, Resmin KhatunSearch for more papers by this authorProf. Sk. Manirul Islam, Prof. Sk. Manirul Islam +91-33-2582-8750 | Fax: +91-33-2582-8282 Search for more papers by this author Swarbhanu Ghosh, Swarbhanu GhoshSearch for more papers by this authorPiyali Bhanja, Piyali Bhanja +91-33-2473-4971 | Fax: +91-33-2473-2805 Search for more papers by this authorRostam Ali Molla, Rostam Ali MollaSearch for more papers by this authorResmin Khatun, Resmin KhatunSearch for more papers by this authorProf. Sk. Manirul Islam, Prof. Sk. Manirul Islam +91-33-2582-8750 | Fax: +91-33-2582-8282 Search for more papers by this author First published: 22 March 2017 https://doi.org/10.1002/slct.201700564AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume2, Issue8March 13, 2017Pages 2588-2588 RelatedInformation

Synthesis of new enantiomerically pure β-amino alcohols of the pinane series

A series of new β-amino alcohols with pinane structure, (+)- and (‒)-3α-amino-10β-pinan-4β-ols, 4β-amino-10β-pinan-3α-ol, and 4α-amino-10β-pinan-3α-ol have been synthesized with the goal of using them as organocatalysts in the aldol reaction of isatin with acetone.

Carane amino alcohols as organocatalysts in asymmetric aldol reaction of isatin with acetone

Carane-derived β-amino alcohols with amino and hydroxy groups at positions 3 and 4 differing in their mutual arrangement and configuration were synthesized. Their application as organocatalysts in the asymmetric aldol reaction of isatin with acetone allowed one to obtain adducts with up to 84% enantiomeric excess.

A novel piperazine linked β-amino alcohols bearing a benzosuberone scaffolds as anti-proliferative agents

A new series of 1-((9-chloro-2,3-dimethyl-6,7-dihydro-5H-benzo[7]annulen-8-yl)methoxy)-3-(4-phenylpiperzin-1-yl) propan-2-ols (6a-k) have been designed, synthesized and their structures were established by spectroscopic data (FT-IR, 1H NMR, 13C NMR, HRMS) and further confirmed by X-ray analysis. The newly synthesized compounds 6a-k were evaluated for their in vitro anti-proliferative activity against four cancer cell lines such as HeLa (cervical), MDA-MB-231 (breast), A549 (lung) and MIAPACA (pancreatic). Among the compounds tested, the compound 6e displayed most potent activity against four cancer cell lines with GI50 values ranging from 0.010 to 0.097μM. The structure and anti-proliferative activity relationship was further supported by in silico molecular docking study of the active compounds against Colchicine binding site of β-tubulin.

Zirconium(IV)-Catalyzed Ring Opening of on-DNA Epoxides in Water.

DNA-encoded library technology (ELT) has spurred wide interest in the pharmaceutical industry as a powerful tool for hit and lead generation. In recent years a number of "DNA-compatible" chemical modifications have been published and used to synthesize vastly diverse screening libraries. Herein we report a newly developed, zirconium tetrakis(dodecyl sulfate) [Zr(DS)4 ] catalyzed ring-opening of on-DNA epoxides in water with amines, including anilines. Subsequent cyclization of the resulting on-DNA β-amino alcohols leads to a variety of biologically interesting, nonaromatic heterocycles. Under these conditions, a library of 137 million on-DNA β-amino alcohols and their cyclization products was assembled.

An efficient method for regioselective ring opening of epoxides by amines under microwave irradiation using Bi(NO3)3·5H2O as a catalyst

Bi(NO3)3·5H2O a highly efficient environmentally benign catalyst, is used for the nucleophilic ring opening of epoxides with aromatic, aliphatic and heteroaromatic amines under solvent free microwave conditions to afford the corresponding β-amino alcohols in good to excellent yields with high regioselectivity.

Task-specific acidic ionic liquid-catalyzed efficient synthesis of β-enaminolactones from alkynoates and β-amino alcohols

An efficient task-specific acidic ionic liquid-catalyzed straightforward synthesis of β-enaminolactones has been demonstrated.

Efficient synthesis of chiral benzofuryl β-amino alcohols via a catalytic asymmetric Henry reaction.

Chiral β-amino alcohol ligands were found effective for the copper(ii)-catalyzed asymmetric Henry reaction of benzofuran-2-carbaldehydes with nitromethane, which led to the formation of (S)-enriched benzofuryl β-nitro alcohols with satisfactory enantioselectivities (up to 98% ee). Using this catalytic protocol, bioactive (S)-benzofuryl β-amino alcohols could be conveniently prepared in short steps.

Synthesis, Antibacterial and Antitubercular Evaluation of Cardanol and Glycerol‑Based β-Amino Alcohol Derivatives

The synthesis of novel amino alcohol derivatives based on cardanol and glycerol were achieved in good yields and characterized by 1H and 13C NMR (nuclear magnetic resonance) and MS (mass spectrometry). In addition, we evaluated the in vitro antimicrobial activity against Gram-positive (Staphylococcus aureus, standard and clinical strains), Gram-negative (Escherichia coli) and M. tuberculosis bacterial strains. The bioassay results indicated that four compounds showed activity against S. aureus, including the clinical resistant strain, with MIC (minimum inhibitory concentration) ranging from 3.90 to 15.60 µg mL-1 and M. tuberculosis, with MIC90 (minimum inhibitory concentration required to inhibit the growth of 90% of organisms) ranging from 3.18 to 7.36 µg mL-1.

Catalytic Chemoselective Conjugate Addition of Amino Alcohols to α,β-Unsaturated Ester: Hydroxy Group over Amino Group and Conjugate Addition over Transesterification.

A highly chemoselective conjugate addition of amino alcohols to α,β-unsaturated ester using a soft Lewis acid/hard Brønsted base cooperative catalyst was developed. This catalysis achieved chemoselective addition of a hydroxy group over an amino group. Moreover, soft metal alkoxide generation enabled chemoselective soft conjugate addition over hard transesterification. Various amino alcohols, including unprecedented cyclic β-amino alcohol, were applicable to the present catalysis.

Silver-catalyzed formal [3+2]-cycloaddition of α-trifluoromethylated methyl isocyanides: a facile stereoselective synthesis of CF3-substituted heterocycles.

An Ag-catalyzed formal [3+2]-cycloaddition of α-trifluoromethylated methyl isocyanides with polar double bonds has been developed for the facile access to trifluoromethylated oxazolines, imidazolines and pyrrolines under mild conditions. The practicality of this chemistry is demonstrated by the gram-scale synthesis of oxazolines with excellent yields and facile transformations of the formed oxazolines to trifluoromethylated β-amino alcohols in quantitative yields.

Synthesis of meta-Functionalized Pyridines by Selective Dehydrogenative Heterocondensation of β- and γ-Amino Alcohols.

New reactions that convert alcohols into important classes of compounds are becoming increasingly important as their development contributes to the conservation of our fossil carbon feedstock and the reduction of CO2 emissions. Two key catalytic alcohol conversion concepts are borrowing hydrogen or hydrogen autotransfer and acceptorless dehydrogenative condensation. Herein, we combined both concepts to synthesize meta-functionalized pyridines. First, diols and amines were linked to β-amino alcohols, which can then undergo a selective dehydrogenative heterocondensation with γ-amino alcohols. Iridium catalysts stabilized by PN5 P pincer ligands that were developed in our laboratory mediate the reactions most efficiently. All of the 3-aminopyridines that we describe in this paper have been synthesized for the first time, emphasizing the degree of innovation of this method and the problems associated with the synthesis of such meta-functionalized pyridines.

Solvent-Directed Epoxide Opening with Primary Amines for the Synthesis of β-Amino Alcohols

An efficient synthesis of β-amino alcohols from a variety of epoxides and primary unbranched amines in the absence of any catalyst in high yields and regioselectivities is reported. A variety of polar mixed solvent systems allow for the selective formation of secondary amino alcohols over tertiary amino alcohols. The reaction scope extends to a wide variety of aromatic and aliphatic substituted epoxides and primary amines bearing complex functionality.

Simple primary β-amino alcohol catalyzed enantioselective Diels-Alder reaction of 3-hydroxy-2-pyridones

The simple primary β-amino alcohol catalyzed Diels-Alder reaction of 3-hydroxy-2-pyridones as dienes with N-substituted maleimides to provide the highly substituted optically active isoquinuclidines as a single diastereomers in excellent enantioselectivities (up to 98%) with excellent chemical yields (up to 95%) was demonstrated. A range of simple β-amino alcohols were synthesized from the corresponding inexpensive amino acids and their catalytic activity was examined for this reaction.

Easy kinetic resolution of some β-amino alcohols by Candida antarctica lipase B catalyzed hydrolysis in organic media

Herein, we present an easy and eco-friendly pathway to obtain some enantiomerically enriched β-amino alcohols using essentially as β-blockers. The enzymatic hydrolysis is conducted in hydrophobic organic media, assisted by sodium carbonate and CAL-B. We describe a new and effective procedure in terms of the chemo- and enantioselectivity, which allows for the formation of both enantiomers: the 2-acetamido-1-arylacetates and 2-acetamido-1-arylethanols were obtained with high ee values (up to >99%), while the selectivities reached E >200. The obtained results show a high CAL-B affinity toward the deacylation of the 2-acetamido-1-arylacetates compared to the acylation one. The structure of the 2-acetamido-1-arylacetates had a significant influence on both reactivity and selectivity of the CAL-B catalyzed deacylation. A multigram scale O-deacylation of racemic 2-acetamido-1-phenylacetate has been carried out, giving access both enantiomers with high enantiomeric purity and good isolated chemical yields.

ChemInform Abstract: Synthesis of Homopropargylamines from 2‐Cyanoazetidines.

AbstractThe tin‐catalyzed reaction of 2‐cyanoazetidines with trimethylsilyl azide gives rise to homopropargylamines via tetrazole formation, azetidine ring opening, extrusion of two molecules of dinitrogen from tetrazol moiety, and Fritsch—Buttenberg—Wiechell rearrangement of carbene to alkyne.

Template Assisted Synthesis of Nanocrystalline Sulfated Titania: Active and Robust Catalyst for Regioselective Ring Opening of Epoxide with Aniline and Kinetic Modeling

The regioselective ring opening of epoxides with aniline affording β-amino alcohols is commercially important. A variety of heterogeneous catalysts such as fuel lean sulfated zirconia (FLSZ), UDCaT-5, 20%Cs2.5H0.5PW12/K-10 clay, Hβ-zeolite, nanocrystalline sulfated titania (NCST), and titania were evaluated in the reaction of epichlorohydrin with aniline. A nanocrystalline sulfated titania (NCST) catalyst, the most active and selective, was prepared by the sol–gel method using poly(vinyl alcohol) (PVA) as a green template and functionalized using sulfuric acid. The sulfate content was in the range 4.1% (w/w). It was well characterized using TEM, FT-IR, XRD, NH3-TPD, N2-BET surface area, and TGA. The effects of various parameters such as speed of agitation, molar ratio, catalyst loading, and temperature using the NCST catalyst were investigated in the reaction of epichlorohydrin with aniline to achieve good yields and excellent regioselectivity at 60 °C and 0.01 g/cm3 catalyst loading. The catalyst was eff...