Catalytic Transformations of Functionalized Cyclic Organic Carbonates

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(42), P. 13735 - 13747

Published: June 6, 2018

Functionalized cyclic organic carbonates and related heterocycles have emerged as highly versatile heterocyclic substrates for ring-opening decarboxylative catalytic transformations allowing the development of new stereo- enantioselective C-N, C-O, C-C, C-S C-B bond formation reactions. Transition-metal-mediated conversions only recently been rejuvenated powerful approaches towards preparation more complex molecules. This minireview will highlight potential structurally with a focus on their synthetic value mechanistic manifolds that are involved upon conversion.

Language: Английский

---

gem-Diborylalkanes: recent advances in their preparation, transformation and application

Organic & Biomolecular Chemistry, Journal Year: 2018, Volume and Issue: 16(7), P. 1050 - 1064

Published: Jan. 1, 2018

Recently,gem-diborylalkanes have attracted much attention as versatile building blocks and fundamental intermediates in organic synthesis, because they enable multiple C–C bond construction further transformation at C–B bonds.

Language: Английский

---

Synthesis and Reactivity of 1,1‐Diborylalkanes towards C–C Bond Formation and Related Mechanisms

Advanced Synthesis & Catalysis, Journal Year: 2017, Volume and Issue: 360(7), P. 1306 - 1327

Published: Dec. 6, 2017

Abstract gem ‐Diborylalkanes have emerged as efficient reagents for synthesizing organoboron compounds through selective C−C bond‐forming reactions. Activation of the 1,1‐diborylalkanes generates carbanions with enhanced stability that are able to react a series electrophiles, carbonyl compounds, imines and epoxides promote formation new bond. These sets reactions become general wide range substrates they can be understood by alternative mechanisms justify potential use these reagents. The C–C(B) bonds achieved chemo‐, diastereo‐ enantioselectivity, because nucleophilc α‐boryl or α‐diboryl attack in stereoselective manner, means catalyst involved. synthesis ‐diborylalkanes has also been promoted innovative methods facilitates access multiborylated different substituents properties. magnified image

Language: Английский

---

Geminal bis(boron) compounds: Their preparation and synthetic applications

Tetrahedron Letters, Journal Year: 2018, Volume and Issue: 59(22), P. 2128 - 2140

Published: April 24, 2018

Language: Английский

---

A Domino Process toward Functionally Dense Quaternary Carbons through Pd-Catalyzed Decarboxylative C(sp³)–C(sp³) Bond Formation

Journal of the American Chemical Society, Journal Year: 2018, Volume and Issue: 140(11), P. 3981 - 3987

Published: Jan. 16, 2018

An efficient protocol was developed to construct functionally dense quaternary carbons with concomitant formation of a new Csp3-Csp3 bond via Pd-catalyzed decarboxylative transformation vinyl cyclic carbonates. This redox-neutral catalytic system features stereocontrolled multisubstituted allylic scaffolds an aldehyde functionality generated in situ, and it typically can be performed at room temperature without any additives. DFT calculations provide rationale toward the selective these compounds reveal complex mechanism that help microkinetic models is able reproduce nontrivial dependence identity product on nature substituents substrate.

Language: Английский

---

Palladium‐Titanium Relay Catalysis Enables Switch from Alkoxide‐π‐Allyl to Dienolate Reactivity for Spiro‐Heterocycle Synthesis

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(26), P. 7860 - 7864

Published: May 10, 2018

Reported herein is the divergent syntheses of [5,5] and [6,5] spiro-heterocycles under Lewis-acid-assisted palladium catalysis. In particular, an unprecedented switch from alkoxide-π-allyl to dienolate reactivity was achieved by use palladium-titanium relay catalysis, represents umpolung vinylethylene carbonates. This method uses a simple procedure commercially available catalysts, delivers both classes spiro-heterocycles, bearing three contiguous stereocenters, in high yield uniformly excellent diastereoselectivity.

Language: Английский

---

Highly tunable multi-borylation of gem-difluoroalkenes via copper catalysis

Nature Catalysis, Journal Year: 2018, Volume and Issue: 1(11), P. 860 - 869

Published: Oct. 26, 2018

Language: Английский

---

Five-Membered Cyclic Carbonates: Versatility for Applications in Organic Synthesis, Pharmaceutical, and Materials Sciences

Applied Sciences, Journal Year: 2021, Volume and Issue: 11(11), P. 5024 - 5024

Published: May 29, 2021

This review presents the recent advances involving several applications of five-membered cyclic carbonates and derivatives. With more than 150 references, it covers period from 2012 to 2020, with special emphasis on use as building blocks for organic synthesis material elaboration. We demonstrate application in important chemical transformations, such decarboxylation, hydrogenation, transesterification reactions, among others. The presence molecules high biological potential is also displayed, together importance these compounds preparation materials urethanes, polyurethanes, flame retardants.

Language: Английский

---

Facile Access to Cyclopropylboronates via Stereospecific Deborylative Cyclization: A Leaving Group‐Assisted Activation of Geminal Diborons

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(21)

Published: March 24, 2023

Herein we reported a transition metal-free deborylative cyclization strategy, based on which two routes have been developed, generating racemic and enantioenriched cyclopropylboronates. The of geminal-bis(boronates) bearing leaving group was highly diastereoselective, tolerating few functional groups applicable to heterocycles. When optically active epoxides were used as the starting materials, cyclopropylboronates could be efficiently prepared with >99 % stereospecificity. Mechanistic studies showed that at γ-position played crucial role significantly promoted activation gem-diboron moiety.

Language: Английский

---

Vinyl and Alkynyl Substituted Heterocycles as Privileged Scaffolds in Transition Metal Promoted Stereoselective Synthesis

Accounts of Chemical Research, Journal Year: 2024, Volume and Issue: 57(5), P. 726 - 738

Published: Feb. 22, 2024

ConspectusBiologically active compounds and pharmaceutically relevant intermediates often feature sterically congested stereogenic centers, in particular, carbon stereocenters that are either tertiary tetrasubstituted ones or quaternary nature. Synthons comprise such bulky structurally complex core units of high synthetic value represent important incentives for communities connected to drug discovery development. Streamlined approaches give access a diverse set incorporating acyclic relatively limited, though vital. They enable further exploration three-dimensional entities can be designed implemented programs, thereby extending the pool molecular properties is inaccessible flat molecules. However, lack modular substrates particular areas chemical space inspired us consider functionalized heterocycles known as cyclic carbonates carbamates productive way create crowded alkenes stereocenters.In this Account, we describe major approximations followed over course 8 years using transition metal (TM) catalysis an instrument control stereochemical various allylic propargylic substitution processes related transformations. Allylic reactions empowered by Pd-catalysis utilizing variety nucleophiles discussed, with amination being seed all combined work. These procedures build on vinyl-substituted (VCCs) simple easy-to-access precursors highly nature compared synthetically limited vinyl oxiranes. Overall these decarboxylative conversions take place "linear" "branched" regioselectivities ligand controlled offer wide scope functional scaffolds. Alternative approaches, including dual TM/photocatalyzed transformations, allowed expand repertoire challenging stereoselective conversions. This was achieved through key single-electron pathways via formal umpolung intermediates, resulting new types carbon–carbon bond formation significantly expanding reactions.Heterocyclic substrate variants have triple groups were also difficult-to-promote TM catalysis. In processes, Nishibayashi laboratory their seminal findings area, discovered reactivity patterns. provided range different stereodefined building blocks 1,2-diborylated 1,3-dienes α-allenols under Cu- Ni-catalysis. realm, use lactone-derived gives elusive chiral γ-amino acids lactams stereofidelity good structural diversity.Apart from efforts, elucidated some pertinent mechanistic manifolds operative transformations better understand limitations opportunities specifically synthons. We both theoretical experimental investigations lead several unexpected outcomes terms enantioinduction models, catalyst preactivation, intimately rationales observed selectivity profiles. The work communicated offers insight into unique carbonates/carbamates acting privileged precursors. It may inspire other members widen toward novel added development academic commercial settings.

Language: Английский

---