1,721,027 research outputs found
Simple Ligand Modifications as a Key to Playing with the Stability of Cu(I), Cu(II), and Cu(III) Organometallic Complexes
No full textProbing the Mechanism of O-2 Activation by a Copper(I) Biomimetic Complex of a C-H Hydroxylating Copper Monooxygenase
No full textFlexibility of N-Heterocyclic Carbene Ligands in Ruthenium Complexes Relevant to Olefin Metathesis and Their Impact in the First Coordination Sphere of the Metal
No full textKOtBu Mediated Alcohol Dehydrogenation Strategy: Synthesis of 2-Aryl Quinazolinones
No full textHerein we report an atom-economical, transition metal-free method for synthesizing 2-aryl quinazolinones through a cascade annulation of 2-amino benzamide and benzyl alcohol. The reaction proceeds via KOtBu-mediated acceptorless alcohol dehydrogenation pathways. The procedure tolerates a wide variety of functional groups and provides a convenient method for the synthesis of 2-aryl quinazolinones. Mechanistic insights by experiments and DFT calculations lead to unveil the reaction mechanism
Rhenium Alkyne Catalysis: Sterics Control the Reactivity
No full textMetathesis reactions, including alkane, alkene, and alkyne metatheses, have their origins in the fundamental understanding of chemical reactions and the development of specialized catalysts. These reactions stand as transformative pillars in organic chemistry, providing efficient rearrangement of carbon-carbon bonds and enabling synthetic access to diverse and complex compounds. Their impact spans industries such as petrochemicals, pharmaceuticals, and materials science. In this work, we present a detailed mechanistic study of the Re(V) catalyzed alkyne metathesis through density functional theory calculations. Our findings are in agreement with the experimental evidence from Jia and co-workers and unveil critical factors governing catalyst performance. Our work not only enhances our understanding of alkyne metathesis but also contributes to the broader landscape of catalytic processes, facilitating the design of more efficient and selective transformations in organic synthesis
Transition metal-free synthesis of 2-aryl quinazolines via alcohol dehydrogenation
No full textWe report here a transition metal-free synthesis of quinazoline derivatives starting from 2-aminobenzyl alcohols and aryl amides via an alcohol dehydrogenation strategy promoted by potassium tertiary butoxide. The control experiments are carried out to identify the reaction intermediates and the role of the K+ ion in the reaction. The DFT calculations unveil the reaction mechanism, with special focus on the rate determining state. The present method tolerates a variety of functional groups providing easy access to diversely substituted quinazolines
Arene vs. Alkene Substrates in Ru-Catalyzed Olefin Metathesis: a DFT Investigation
No full textDFT calculations have been performed to compare metathesis of olefin, diene, and arene substrates catalyzed by a 2nd generation Ru(SIMes)-based complex. A large screening of modified substrates has been performed with the intention to explore the energetic gaps between acyclically conjugated alkenes and arenes in metathesis processes. The results are analyzed through the effects of conjugation vs. aromaticity, as quantified by the HOMA and NICS aromaticity indices, as well as the effects of non-covalent interactions between coplanar rings and/or any ring with functional groups nearby
A comparison of the performance of the semiempirical PM6 method versus DFT methods in Ru-catalyzed olefin metathesis
No full textAccess to Secondary Amines through Hydrogen Autotransfer Reaction Mediated by KOtBu
No full textWe report herein an N-alkylation reaction of amines with alcohols through a hydrogen autotransfer reaction. Unlike other catalytic systems containing transition metals or additives, potassium tertiary butoxide was found to be a unique and effective catalyst for synthesizing secondary amines. The role of the K+ ion and the reaction intermediates were studied under control experiments and by theoretical calculations. The reaction was found to be general and tolerates a series of functional groups, providing a convenient method to synthesize N-alkylated compounds
Exploring the Reactivity of Ru-Based Metathesis Catalysts with a pi-Acid Ligand Trans to the Ru-Ylidene Bond
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