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Chemical equations are presented for the article "Medium-Ring Stereocontrol in the Temporary Silicon-Tethered Ring-Closing Metathesis Approach to the Synthesis of Polyketide Fragments" by P.A. Evans and colleagues, published in the periodical "Synthesis."

A concise total synthesis of dendrodolides A-D (Ia)-(Id) is achieved in 10 steps starting from (R)-propylene oxide and 3-buten-1-ol utilizing Jacobsen hydrolytic kinetic resolution, epoxide opening with 2-allyl-1,3-dithiane, Yamaguchi esterification, and ring-closing metathesis (RCM) as the key steps. [ABSTRACT FROM AUTHOR]

An asymmetric carbene cascade reaction, which proceeds through a carbene/alkyne metathesis and a formal [3+2] cycloaddition and converts alkynyl-tethered enol diazoacetates to chiral bicyclic cyclopentadienes, is presented. [ABSTRACT FROM AUTHOR]

The preparation of a potentially versatile α-substituted α,β-unsaturated lactam is described. [ABSTRACT FROM AUTHOR]

Upon addition of a chiral amine ligand, an alcohol and a base, the 1st generation Hoveyda-Grubbs catalyst is in situ transformed into an asymmetric transfer hydrogenation catalyst, promoting the enantioselective reduction of acetophenone to 1-phenylethanol. [ABSTRACT FROM AUTHOR]

An asymmetric synthesis of (I) is presented starting from (S)-2-hydroxypropanoate via Horner-Wadsworth-Emmons olefination, Sharpless dihydroxylation, zinc allylation, and ring-closing metathesis. [ABSTRACT FROM AUTHOR]

An asymmetric total synthesis of (I) is performed starting from D-(+)-gluconic acid δ-lactone via Yamaguchi esterification and ring-closing metathesis as the key steps. [ABSTRACT FROM AUTHOR]

Prochiral olefins generated by metathesis are highly enantioselectively hydrogenated by an in situ obtained chiral ruthenium catalyst. [ABSTRACT FROM AUTHOR]

Ruthenium catalyzes both the metathesis reaction as well as the dihydroxylation reaction upon addition of NaIO4. [ABSTRACT FROM AUTHOR]

The article presents a diagram which shows the molecular structure of the synthesis of bioactive neolignans and its diastereoselective route to trans-2-Aryl-2,3-dihydrobenzofurans through sequential cross-metathesis/isomerization/allylboration reactions.

The article presents the process of using salt as a Hydride and a Carbon di oxide (CO2) along which the reaction of Hydrocarboxylation.

An abstract of the article "Simultaneous Induction of Axial and Planar Chirality in Arene-Chromium Complexes by Molybdenum-Catalyzed Enantioselective Ring-Closing Metathesis" by K. Kamikawa and colleagues is presented.

The article presents a chemical formula related to the article "Catalyst-Controlled Stereoselective Olefin Metathesis as a Principal Strategy in Multistep Synthesis Design: A Concise Route to (+)-Neopeltolide" by M. Yu and others, in the periodical "Angewandte Chemie International Edition" in 2015.

The synthesis of the title compound (VI) is based on the highly diastereoselective addition of allylzinc bromide to bisimine (I) and ring-closing metathesis as the key steps. [ABSTRACT FROM AUTHOR]

A ligand-directed, metal-catalyzed asymmetric intermolecular hydroalkoxylation of alkoxyallene and subsequent ring-closing metathesis offers a new atom-efficient method toward cyclic acetals with unique anomeric control. [ABSTRACT FROM AUTHOR]

A straightforward strategy for the synthesis of different diastereomers of 4-hydroxy-2,6-disubstituted pyrans is described. [ABSTRACT FROM AUTHOR]

The article presents a chemical reaction of vinylcyclopropanes by using ring-closing metathesis.

Enantioenriched complexes incorporating cyclometalated NHC ligands catalyze (Z)- and enantioselective asymmetric ring opening/cross metathesis reactions of norbornenes and cyclobutenes, and the difference in ring strain between these two compounds leads to different propagating species in the catalytic cycle. [ABSTRACT FROM AUTHOR]

The enantioselective addition of styrylboronic acid (II) to symmetrical and unsymmetrical dienones, catalyzed by O-monoacyltartaric acid, affords monostyrylated adducts [ct. [ABSTRACT FROM AUTHOR]

An efficient asymmetric allylic alkylation of Morita-Baylis-Hillman adducts with allyl and homoallyl malononitrile is developed. [ABSTRACT FROM AUTHOR]

The target compound is synthesized in 17 steps and 10.1% overall yield starting from (+)-Roche ester. [ABSTRACT FROM AUTHOR]

A one-pot four-step multi-reaction process involving a thermal Overman rearrangement, a tandem metathesis reaction, and a Diels-Alder reaction is developed for the diastereoselective synthesis of aminobicyclononanes and -decanes with up to five stereogenic centers. [ABSTRACT FROM AUTHOR]

Enantiopure α-substituted β-hydroxy esters, which are obtained by biocatalytic reduction with Klebsiella pneumoniae, serve as chirons for preparation of oxetanes (II), carbohydrate mimic (V), ε-lactone (VII) and cyclitols (X), (XI), and (XV). [ABSTRACT FROM AUTHOR]

This new gold-catalyzed intramolecular allylic alkylation reaction provides chiral chromans for the synthesis of α-tocopherol [vitamin E (IVc)], γ-tocopherol (IVe), and its analogs (VII), as well as trolox (VIII) and (S)-LLU-a (IX) via a following metathesis reaction. [ABSTRACT FROM AUTHOR]

An efficient method for the diastereoselective synthesis of cis-4-methyl- as well as cis-4-mercaptopipecolic acid esters [cf. [ABSTRACT FROM AUTHOR]

The key steps of the synthesis of the title fragment (I) are cross metathesis and Bu4NF promoted oxa-Michael reaction. [ABSTRACT FROM AUTHOR]

The recently published route towards α,α-disubstituted α-amino acids via umpolung N-alkylation followed by asymmetric allylic alkylation is combined with cross-metathesis and ring-closing metathesis, respectively, broadening the allylic diversity and giving even access to higher ring homologes of α-substituted prolines. [ABSTRACT FROM AUTHOR]

The reaction of alcohol (I) with N,N′-thiocarbonyldiimidazole is accompanied by a [3,4]-sigmatropic rearrangement to afford imidazoles (III), which are readily converted into thiocarbamates (V). [ABSTRACT FROM AUTHOR]

The total syntheses of the monoterpene indole alkaloids leuconoxine (IX), leuconodine B (VIII) and melodinine E (X) are described. [ABSTRACT FROM AUTHOR]

The synthesis of spiroketals, spiroethers, and oxabicylcles is achieved via enantioselective cyclization of functionalized enones like (VII) to dihydropyrans followed by ring closing metathesis, Prins reaction, or spiroketalization. [ABSTRACT FROM AUTHOR]

The utility of this reaction is demonstrated by a short synthesis of L-ribose derivative (VII). [ABSTRACT FROM AUTHOR]

The article highlights the chemical equations involved in the total synthesis of the isodon diterpene sculponeatin N.

The target compound is prepared in 11 steps and 14% overall yield starting from D-glyceraldehyde acetonide. [ABSTRACT FROM AUTHOR]

All the products are obtained with excellent (Z)-selectivities. [ABSTRACT FROM AUTHOR]

A new synthesis of the open precursors of the title compound is presented. [ABSTRACT FROM AUTHOR]

Using a known pathway, chiral diol (II) can be easily obtained via Noyori reduction which establishes the product stereochemistry in a single step. [ABSTRACT FROM AUTHOR]

The synthesis of the cyclopentane subunit (IV) of jatrophane diterpenes is described using Grubbs′ enyne metathesis of alkyne (I) and stereoselective Pd-catalyzed ring opening of the epoxide (III) as key steps. [ABSTRACT FROM AUTHOR]

The synthesis of the title compounds is achieved via alkylmagnesium chloride addition/RCM sequence. [ABSTRACT FROM AUTHOR]

In some cases the two step procedure is performed in one pot without quenching the reaction mixture after the allylic alkylation step before the Grubbs catalyst is added. [ABSTRACT FROM AUTHOR]

The article presents a series of chemical equations for the synthesis of 3-hydroxypiperidines through iridium-catalyzed allylic substitution.

A diagram is presented which shows a resolved stereogenic-at-ruthenium complex-catalyzed enantioselective and high Z-selective ring-opening/cross-metathesis.

using a catalytic system of Hoveyda-Grubbs 2nd generation catalyst and a chiral BINOL-derived phosphoric acid [ABSTRACT FROM AUTHOR]

A stepwise process consisting of asymmetric allylation of imines of type (I) and following ring-closing metathesis of the resulting dienes (III) is developed to synthesize cyclic homoallylic amines. [ABSTRACT FROM AUTHOR]

A novel sequence of tandem transformations, combining a first Petasis borono-Mannich/intramolecular Diels-Alder transformation and subsequently a cross-metathesis/conjugate addition reaction is reported. [ABSTRACT FROM AUTHOR]

Asymmetric syntheses of amino-methyl-cyclopentanecarboxylic acids are achieved in 9 steps from commercially available starting materials via Ireland-Claisen rearrangement of β-amino allyl esters (I), followed by ring-closure metathesis, reduction and deprotection. [ABSTRACT FROM AUTHOR]

A simple synthesis of enantiopure unsaturated lactone (VII) and its enantiomer employing Maruoka asymmetric allylation and subsequent ring closing metathesis as the key steps is given. [ABSTRACT FROM AUTHOR]

The article presents chemical equation for the synthesis of azaheterocyclic vinylphosphonates by ring-closing metathesis.

Diels-Alder adducts of masked o-benzoquinones are demethoxylated and allylated to serve as precursors for a highly efficient synthesis of the desired structural unit. [ABSTRACT FROM AUTHOR]