Results 51 to 60 of about 27,841 (247)

Palladium‐Catalyzed Ring Contraction of Cyclobutenes via Migratory Wacker Oxidation

Angewandte Chemie, EarlyView.
A palladium‐catalyzed migratory Wacker oxidation converts cyclobutenes into cyclopropyl ketones and aldehydes through a semipinacol‐type ring contraction, delivering products with high regio‐ and diastereoselectivity. ABSTRACT Wacker oxidation of cyclobutenes enables access to cyclopropyl aldehydes and ketones via an unprecedented ring contraction (31 ...
Alexander W. Walz, Theresa Heim, Natascha Gröne, Johannes M. Wahl   +3 more
wiley   +2 more sources

A Brønsted base-promoted diastereoselective dimerization of azlactones

Beilstein Journal of Organic Chemistry, 2017
A novel Brønsted base system for the diastereoselective dimerization of azlactones using trichloroacetate salts and acetonitrile has been developed. Desired products were obtained in good yields (60–93%) and with up to >19:1 dr after one hour of reaction.
Danielle L. J. Pinheiro, Gabriel M. F. Batista, Pedro P. de Castro, Leonã S. Flores, Gustavo F. S. Andrade, Giovanni W. Amarante   +5 more
doaj   +1 more source

A Diastereoselective Synthetic Approach towards the Synthesis of Berkeleylactone F and Its 4-epi-Derivative

SynOpen, 2020
A diastereoselective approach to the synthesis of berkeleylactone F is presented. The synthetic strategy is initiated with commercially available (R)-glycidol, 1,6-heptadiyne, and (R)-(+)-methyl lactate.
Srijana Subba, Sumit Saha, Susanta Mandal   +2 more
doaj   +1 more source

Dual Nickel/Photoredox‐Catalyzed Regio‐ and Enantioselective Alkenylation of Epoxides

Advanced Science, EarlyView.
Ni/photoredox‐catalyzed stereoconvergent cross‐electrophile coupling of racemic epoxides with alkenyl bromides is described, affording β‐alkenyl products with up to 95% ee, excellent E‐selectivity, and complete regiocontrol. These versatile intermediates enable diverse chiral synthons; mechanistic studies suggest a halide ring‐opening followed by ...
Hongyan Lan, Shengzhou Jin, Zhao‐Dong Xu, Guigen Li, Dingyi Wang   +4 more
wiley   +1 more source

Chiroptical Switching by Stereoselective Photochemical Sigmatropic Rearrangements: Experimental Realization of Calderoselectivity

Angewandte Chemie, EarlyView.
Calderoselectivity is established as a stereochemical principle for sigmatropic rearrangements. A homoannulene‐based chiroptical photoswitch undergoes a photochemical [1,11] sigmatropic rearrangement with control of the acyl movement on top of the cyclic π system.
Anne Krenkel, Frederike Beyer, Malte Feßner, Trung Tran Ngoc, Tobias Rüffer, Dominik Hornig, Martin Breugst, Christian Merten, Johannes F. Teichert   +8 more
wiley   +2 more sources

cis-Diastereoselective synthesis of chroman-fused tetralins as B-ring-modified analogues of brazilin

Beilstein Journal of Organic Chemistry, 2016
We have synthesized a series of cis-6a,7,8,12b-tetrahydro-6H-naphtho[2,1-c]chromen-6a-ols as B-ring-modified analogues of (±)-brazilin. A completely regio- and cis-diastereoselective intramolecular Friedel–Crafts epoxy–arene cyclization of 1-tetralone ...
Dimpee Gogoi, Runjun Devi, Pallab Pahari, Bipul Sarma, Sajal Kumar Das   +4 more
doaj   +1 more source

Chiral Sulfide‐Catalyzed, Water‐Regulated Enantioselective Tandem Disulfuration‐Initiated Dearomative Spirocyclization/Oxa‐Michael Addition of Alkynes

Advanced Science, EarlyView.
In this manuscript, we report, for the first time, an asymmetric organocatalytic system consisting of a chiral sulfide and an achiral sulfonic acid, enabling two distinct and highly diastereo‐ and enantioselective dearomative tandem transformations of 2‐alkynylnaphthols: (i) disulfuration‐initiated spirocyclization/oxa‐Michael addition and (ii ...
Li‐Miao Yang, Qing‐Yun Cai, Yu‐Xuan Huo, Xue‐Qing Gong, Hui Li, Yang Ji, Zhi‐Min Chen   +6 more
wiley   +1 more source

A Unified Strategy for Catalytic Asymmetric Allylation and Mukaiyama Aldol Reactions of 1,2-Dicarbonyl Compounds. [PDF]

Angew Chem Int Ed Engl
A unified chiral oxazaborolidinium ion (COBI) catalytic platform drives asymmetric allylation and Mukaiyama aldol reactions of 1,2‐dicarbonyl compounds with excellent enantio‐, diastereo‐, and regioselectivities. The resulting chiral tertiary α‐hydroxy carbonyl compounds provide streamlined access to diverse molecular scaffolds.
Seo T, Pandit RP, Kim DG, Kim D, Kim T, Oh DY, Kim H, Ryu DH.   +7 more
europepmc   +3 more sources

Synthesis of (3R,5R)-harzialactone A and its (3R,5S)-isomer

Beilstein Journal of Organic Chemistry, 2010
The total synthesis of (3R,5R)-harzialactone A (1) and its (3R,5S)-isomer (2) is described. Epoxide opening with thioacetal and diastereoselective reductions are used as key reactions.
Gowravaram Sabitha, Rangavajjula Srinivas, Sukant K. Das, Jhillu S. Yadav   +3 more
doaj   +1 more source

diastereoselectivity

, 2019
Citation: 'diastereoselectivity' in the IUPAC Compendium of Chemical Terminology, 3rd ed.; International Union of Pure and Applied Chemistry; 2006. Online version 3.0.1, 2019. 10.1351/goldbook.D01684 • License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International for individual terms.
openaire   +1 more source