Domino Heck−Aza-Michael Reactions: Efficient Access to 1-Substituted Tetrahydro-β-carbolines

2010 ◽  
Vol 75 (5) ◽  
pp. 1787-1790 ◽  
Author(s):  
Daniel L. Priebbenow ◽  
Luke C. Henderson ◽  
Frederick M. Pfeffer ◽  
Scott G. Stewart
Keyword(s):  
Michael Reactions ◽  
Efficient Access

ChemInform Abstract: Rapid and Efficient Access to meso-2,5-cis-Disubstituted Pyrrolidines by Double Aza-Michael Reactions of Chiral Primary Amines.

ChemInform ◽  
2008 ◽  
Vol 39 (19) ◽  
Author(s):  
Leila Cabral dos Santos ◽  
Zineb Bahlaouan ◽  
Khadija El Kassimi ◽  
Claire Troufflard ◽  
Frederic Hendra ◽  
...  
Keyword(s):  
Primary Amines ◽  
Michael Reactions ◽  
Efficient Access

ChemInform Abstract: Domino Heck-Aza-Michael Reactions: Efficient Access to 1-Substituted Tetrahydro-β-carbolines.

ChemInform ◽  
2010 ◽  
Vol 41 (25) ◽  
pp. no-no
Author(s):  
Daniel L. Priebbenow ◽  
Luke C. Henderson ◽  
Frederick M. Pfeffer ◽  
Scott G. Stewart
Keyword(s):  
Michael Reactions ◽  
Efficient Access

Rapid and Efficient Access to Meso-2,5-cis-disubstituted Pyrrolidines by Double Aza-Michael Reactions of Chiral Primary Amines

Heterocycles ◽  
2007 ◽  
Vol 73 (1) ◽  
pp. 751 ◽  
Author(s):  
Delphine Joseph ◽  
Leila Cabral dos Santos ◽  
Zineb Bahlaouan ◽  
Khadija El Kassimi ◽  
Claire Troufflard ◽  
...  
Keyword(s):  
Primary Amines ◽  
Michael Reactions ◽  
Efficient Access

Sequential C-Selective Difluoromethylation/Pd-Catalyzed Decarboxylative Protonation: An Efficient Access to Tertiary Difluoromethylated Scaffolds

2019 ◽  
Author(s):  
Nicolas Duchemin ◽  
Roberto Buccafusca ◽  
Marc Daumas ◽  
Vincent Ferey ◽  
Stellios Arseniyadis
Keyword(s):  
Drug Development ◽  
Late Stage ◽  
Efficient Access ◽  
Palladium Catalyzed ◽  
General Method

We report here a general method that allows a highly straightforward access to tertiary difluoromethylated compounds. The strategy relies on a two-step sequence featuring a C-selective electrophilic difluoromethylation and an unprecedented palladium-catalyzed decarboxylative protonation. Considering the generality of the method and the attractive properties offered by the difluoromethyl group, this approach provides a valuable tool for late-stage functionalization and drug development.<br>

Enantioselective Michael Addition of Malonates to Enones

2020 ◽  
Vol 24 (7) ◽  
pp. 746-773
Author(s):  
Péter Bakó ◽  
Tamás Nemcsok ◽  
Zsolt Rapi ◽  
György Keglevich
Keyword(s):  
Michael Addition ◽  
Activity Relationship ◽  
Chalcone Derivatives ◽  
Michael Additions ◽  
Michael Reactions ◽  
Structure Activity ◽  
Cyclic Enones ◽  
Michael Acceptors ◽  
Relationship Of ◽  
Enantioselective Catalysts

: Many catalysts were tested in asymmetric Michael additions in order to synthesize enantioenriched products. One of the most common reaction types among the Michael reactions is the conjugated addition of malonates to enones making it possible to investigate the structure–activity relationship of the catalysts. The most commonly used Michael acceptors are chalcone, substituted chalcones, chalcone derivatives, cyclic enones, while typical donors may be dimethyl, diethyl, dipropyl, diisopropyl, dibutyl, di-tert-butyl and dibenzyl malonates. This review summarizes the most important enantioselective catalysts applied in these types of reactions.

Electrochemical Oxidative Esterification of Thiophenols: Efficient Access to Sulfinic Esters

2020 ◽  
Vol 17 (7) ◽  
pp. 540-547
Author(s):  
Chun-Hui Yang ◽  
Cheng Wu ◽  
Jun-Ming Zhang ◽  
Xiang-Zhang Tao ◽  
Jun Xu ◽  
...  
Keyword(s):  
Organic Synthesis ◽  
Efficient Method ◽  
High Efficiency ◽  
Building Blocks ◽  
Constant Current ◽  
Good Efficiency ◽  
Oxidative Esterification ◽  
Efficient Access ◽  
New Applications ◽  
Sulfinic Esters

Background: The sulfinic esters are important and useful building blocks in organic synthesis. Objective: The aim of this study was to develop a simple and efficient method for the synthesis of sulfinic esters. Materials and Methods: Constant current electrolysis from thiols and alcohols was selected as the method for the synthesis of sulfinic esters. Results and Discussion: A novel electrochemical method for the synthesis of sulfinic esters from thiophenols and alcohols has been developed. Up to 27 examples of sulfinic esters have been synthesized using the current methods. This protocol shows good functional group tolerance as well as high efficiency. In addition, this protocol can be easily scaled up with good efficiency. Notably, heterocycle-containing substrates, including pyridine, thiophene, and benzothiazole, gave the desired products in good yields. A plausible reaction mechanism is proposed. Conclusion: This research not only provides a green and efficient method for the synthesis of sulfinic esters but also shows new applications of electrochemistry in organic synthesis. It is considered that this green and efficient synthetic protocol used to prepare sulfinic esters will have good applications in the future.

scholarly journals The impact of COVID-19 related national lockdown on ophthalmic emergency in Italy: A multicenter study

2021 ◽  
pp. 112067212110280
Author(s):  
Maria L Salvetat ◽  
Carlo Salati ◽  
Patrizia Busatto ◽  
Marco Zeppieri
Keyword(s):  
Gender Bias ◽  
Tertiary Care ◽  
Lower Number ◽  
Electronic Records ◽  
Chi Square ◽  
Efficient Access ◽  
Chi Square Test ◽  
Unpaired Student ◽  
The Impact ◽  
Wet Amd

Purpose: To assess ocular pathologies admitted to Italian Emergency Eye Departments (EEDs) during the COVID-19 pandemic national lockdown in 2020 in comparison with the same period in 2019. Methods: Electronic records of all patients presenting at EEDs of two tertiary-care Eye Centers during the COVID-19 national lockdown in Italy (March 10–May 3, 2020) were compared with the equivalent period in 2019. Main outcomes were patient age, gender, and diagnoses. Statistical analysis included unpaired Student t-tests, Poisson regression, and chi-square test. Results: Overall EED visits significantly decreased by 54.1% during the 2020 lockdown compared to 2019 (851 vs 1854, p < 0.001). During lockdown, patients showed comparable mean age (52.8 years in 2020 vs 53.3 years in 2019, p = 0.52) and significant male gender bias (61.1% in 2020 vs 55.8% in 2019, p < 0.0001). The most frequent pathologies were eye inflammations, trauma-related incidents, and spontaneous acute vitreous detachment. Patients with inflammation, headache/hemicrania, and spontaneous subconjunctival hemorrhages were significantly less, whereas those with trauma-related diagnoses were significantly higher during the lockdown as compared with 2019 ( p < 0.05). The proportion of non-urgent visits decreased from 17% in 2019 to 8% in 2020 ( p < 0.001). Conclusions: During the 2020 lockdown, there was a significant reduction of accesses to EED, especially for non-urgent pathologies. Potentially visual function threatening conditions, such as trauma-related pathologies, retinal detachment or ruptures, and wet AMD, showed lower number of cases but higher or stable proportion relative to the total caseload, suggesting a correct and efficient access to ophthalmic health care during the pandemic period.

scholarly journals Stereoselective Tandem Iridium-Catalyzed Alkene Isomerization-Cope Rearrangement of ω-diene Epoxides: Efficient Access to Acyclic 1,6-Dicarbonyl Compounds

2021 ◽  
Author(s):  
Rahul Suresh ◽  
Itai Massad ◽  
Ilan Marek
Keyword(s):  
Bond Cleavage ◽  
Cope Rearrangement ◽  
Dicarbonyl Compounds ◽  
Alkene Isomerization ◽  
Efficient Access

The Cope rearrangement of 2,3-divinyloxiranes, a rare example of epoxide C-C bond cleavage, results in 4,5-dihydrooxepines which are amenable to hydrolysis, furnishing 1,6-dicarbonyl compounds containing two contiguous stereocenters at the 3- and 4- positions. We employ...

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