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Annulation

About: Annulation is a research topic. Over the lifetime, 10152 publications have been published within this topic receiving 189701 citations.


Papers
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Journal ArticleDOI
TL;DR: Racemization required: Rhodium(I)-catalyzed C-H activation directed by unprotected ketimines initiates selective [3+2] cycloaddition with allenes, providing access to highly substituted indenylamines.
Abstract: Keywords: allenes ; asymmetric catalysis ; CH activation ; DYKAT ; rhodium Reference EPFL-ARTICLE-190184doi:10.1002/anie.201304919View record in Web of Science Record created on 2013-11-04, modified on 2017-05-12

116 citations

Journal ArticleDOI
TL;DR: The asymmetric annulation of a range of α,β-unsaturated acyl ammonium intermediates, formed from isothiourea HBTM 2.1 and anhydrides with either 1,3-dicarbonyls, β-ketoesters or azaaryl ketones gives either functionalised esters (upon ring opening), dihydropyranones or dihydrophyridones in good yields and high enantioselectivity (up to 97% ee) as mentioned in this paper.
Abstract: The asymmetric annulation of a range of α,β-unsaturated acyl ammonium intermediates, formed from isothiourea HBTM 2.1 and anhydrides with either 1,3-dicarbonyls, β-ketoesters or azaaryl ketones gives either functionalised esters (upon ring opening), dihydropyranones or dihydropyridones in good yields (up to 93%) and high enantioselectivity (up to 97% ee).

116 citations

Journal ArticleDOI
Zhuo-Zhuo Zhang1, Bin Liu1, Jing-Wen Xu1, Sheng-Yi Yan1, Bing-Feng Shi1 
TL;DR: A mild Co(III)-catalyzed oxidative annulation of N-arylureas and internal alkynes has been developed, providing a new opportunity for the synthesis of diverse indoles.

116 citations

Journal ArticleDOI
TL;DR: The total synthesis of the terpene indole alkaloid (+)-ibophyllidine is performed through a pathway involving asymmetric phosphine catalysis, with the novel l-4-hydroxyproline-derived chiral phosphine mediating the key [3 + 2] annulation.
Abstract: In this study we performed the total synthesis of the terpene indole alkaloid (+)-ibophyllidine through a pathway involving asymmetric phosphine catalysis, with our novel L-4-hydroxyproline-derived chiral phosphine mediating the key [3 + 2] annulation. Hydrogenation of the [3 + 2] adduct allowed the rapid formation of the stereochemically dense pyrrolidine ring of (+)-ibophyllidine in excellent yield with exceptionally high levels of both diastereo- and enantioselectivity. We constructed the remainder of the pentacyclic skeleton through an intramolecular alkylation and an intramolecular aza-Morita–Baylis–Hillman reaction.

116 citations

Journal ArticleDOI
TL;DR: A comprehensive review of the literature on DMSO-based Oxidations can be found in this article, where the authors systematically summarized synthetic transformations that have utilized the fragments of dimethyl sulfoxide as building blocks.
Abstract: Dimethyl sulfoxide is generally characterized as a solvent and oxidant rather than as a substrate, building block, or synthon in organic chemistry. However, an abundance of reports have recently appeared that demonstrate dimethyl sulfoxide acting in these roles. This review article offers a comprehensive summary of the literature on this topic until the end of 2015. Synthetic transformations that have utilized the ‘C–S–C’, ‘C’, and ‘C–S’ fragments of dimethyl sulfoxide as building blocks are systematically summarized. 1 Introduction 2 History and Recent Highlights of DMSO-Based Oxidations 3 DMSO-Based Methylthiomethylation (–CH2SMe) 4 DMSO as a One-Carbon Synthon 4.1 DMSO-Based Methylation (–Me) 4.2 DMSO-Based Methylenation (–CH2–) 4.3 DMSO-Based Annulation/Aromatization (=CH–) 4.4 DMSO-Based Formylation (–CHO) 4.5 DMSO-Based Cyanation (–CN) 5 DMSO as Synthon for ‘S–C’ Functionalities 5.1 DMSO-Based Thiomethylation (–SMe) 5.2 DMSO-Based Methylsulfonylation (–SO2Me) 6 Summary and Conclusions

115 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023468
2022850
2021754
2020618
2019699
2018603