Effects of Water Addition on a Catalytic Fluorination of Dienamine

Kuraoku, Daiki; Yonamine, Tsunaki; Koja, Genta; Yoshida, Norio; Arimitsu, Satoru; Higashi, Masahiro

doi:10.3390/molecules24193428

Cited by 7 publications

(6 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Arimitsu, Higashi et al described regio- and enantioselective α-fluorination reactions of α-methyl α,β-enals with N -fluoro bis(phenylsulfonyl)imide (NSFI) via the corresponding dienamine intermediate ( Scheme 41 ) [ 118 , 119 ]. Dienamines formed upon the condensation of enals with a primary amine catalyst are nucleophilic at both α- and γ-carbons.…”

Section: Methods Based On Dual Enamine Activation/brønsted Acid Catal...mentioning

confidence: 99%

Catalytic Asymmetric α-Functionalization of α-Branched Aldehydes

et al. 2023

View full text Add to dashboard Cite

Aldehydes constitute a main class of organic compounds widely applied in synthesis. As such, catalyst-controlled enantioselective α-functionalization of aldehydes has attracted great interest over the years. In this context, α-branched aldehydes are especially challenging substrates because of reactivity and selectivity issues. Firstly, the transient trisubstituted enamines and enolates resulting upon treatment with an aminocatalyst or a base, respectively, would exhibit attenuated reactivity; secondly, mixtures of E- and Z-configured enamines/enolates may be formed; and third, effective face-discrimination on such trisubstituted sp2 carbon intermediates by the incoming electrophilic reagent is not trivial. Despite these issues, in the last 15 years, several catalytic approaches for the α-functionalization of prostereogenic α-branched aldehydes that proceed in useful yields and diastereo- and enantioselectivity have been uncovered. Developments include both organocatalytic and metal-catalyzed approaches as well as dual catalysis strategies for forging new carbon–carbon and carbon–heteroatom (C-O, N, S, F, Cl, Br, …) bond formation at Cα of the starting aldehyde. In this review, some key early contributions to the field are presented, but focus is on the most recent methods, mainly covering the literature from year 2014 onward.

show abstract

Section: Methods Based On Dual Enamine Activation/brønsted Acid Catal...mentioning

confidence: 99%

Catalytic Asymmetric α-Functionalization of α-Branched Aldehydes

et al. 2023

View full text Add to dashboard Cite

show abstract

“…Subsequent DFT calculations of the transition states with a counterion showed that TS‐ R ‐A − is slightly lower in energy than TS‐ S ‐A − ( A − represents a counterion) (ii, Figure 4). [35,37] MeSO 3 − was chosen for the calculation because of the similarity of its enantioselectivity to that of A1 and the lower computational time requirements. The findings suggest that MeSO 3 − preferentially stabilizes the TS‐ R ‐A − configuration, with a significant contribution from the non‐classical C−H⋅⋅⋅O hydrogen bonds outlined in the table in Figure 4.…”

Section: Chemistry Of Allylic Fluoridesmentioning

confidence: 99%

“…Initially, the transition states were calculated without considering the effect of the counterions produced by the Brønsted acid (i, Figure 4). [35,37] Interestingly, the activation free energy of TS-S was found to be lower than that of TS-R because of the larger steric hindrance of NH with the remote olefinic moiety compared to that of Me α . However, this result is not in accordance with the experimental outcome.…”

Section: P E R S O N a L A C C O U N T T H E C H E M I C A L R E C O R Dmentioning

confidence: 99%

“…Subsequent DFT calculations of the transition states with a counterion showed that TS-R-A À is slightly lower in energy than TS-S-A À (A À represents a counterion) (ii, Figure 4). [35,37] MeSO 3 À was chosen for the calculation because of the similarity of its enantioselectivity to that of A1 and the lower computational time requirements. The findings suggest that MeSO 3…”

Section: P E R S O N a L A C C O U N T T H E C H E M I C A L R E C O R Dmentioning

confidence: 99%

See 1 more Smart Citation

Syntheses and Synthetic Applications of Functionalized Propargylic and Allylic Fluorides

Arimitsu

2023

The Chemical Record

Self Cite

View full text Add to dashboard Cite

This account presents the synthesis and application of propargylic and allylic fluorides containing hydroxy or carbonyl functional groups. In particular, the Barbier‐type reaction of difluoropropargyl bromides with aldehydes or chloroformates provides versatile propargylic fluorides, and the organocatalytic fluorination of dienamine intermediates has been demonstrated as an effective method to obtain allylic fluorides stereoselectively. Additionally, mechanistic insights into such reactions are discussed with the aid of density functional theory calculations. The report also describes the preparation of fluorinated 1,7‐diyne or 1,7‐enyne derivatives of these compounds. These propargylic and allylic fluorides can be used as building blocks for fluorinated heterocycles, such as fluorinated furans, tetrahydrofurans, and lactams. Additionally, fluorinated bi‐ or tri‐heterocyclic compounds can be synthesized via transition‐metal‐catalyzed reactions with fluorinated 1,7‐diyne or 1,7‐enyne derivatives.

show abstract

“…There exists a close relationship between the molecular structure and the macro properties of the epoxy resin. As a mature process, surface fluorination technology has been proved to be efficient for the modification of polymer materials in various researches, showing priorities of the simple operation and the low cost [14][15][16]. Studies have shown that in the fluorination process, F atoms can be introduced into the material and polymer chain breaking and crosslinking reactions may occur.…”

Section: Introductionmentioning

confidence: 99%

Molecular Structure Modulated Trap Distribution and Carrier Migration in Fluorinated Epoxy Resin

Wang

Ran

et al. 2020

Molecules

View full text Add to dashboard Cite

Surface charge accumulation on epoxy insulators is one of the most serious problems threatening the operation safety of the direct current gas-insulated transmission line (GIL), and can be efficiently inhibited by the surface modification technology. This paper investigated the mechanisms of fluorination modulated surface charge behaviors of epoxy resin through quantum chemical calculation (QCC) analysis of the molecular structure. The results show that after fluorination, the surface charge dissipation process of the epoxy sample is accelerated by the introduced shallow trap sites, which is further clarified by the carrier mobility model. The electron distribution probability of the highest occupied molecular orbitals (HOMO) under positive charging and the lowest unoccupied molecular orbitals (LUMO) under negative charging shows distinctive patterns. It is illustrated that electrons are likely to aggregate locally around benzenes for the positively charged molecular structure, while electrons tend to distribute all along the epoxy chain under negatively charging. The calculated results verify that fluorination can modulate surface charge behaviors of epoxy resin through redesigning its molecular structure, trap distribution and charging patterns.

show abstract

Effects of Water Addition on a Catalytic Fluorination of Dienamine

Cited by 7 publications

References 20 publications

Catalytic Asymmetric α-Functionalization of α-Branched Aldehydes

Catalytic Asymmetric α-Functionalization of α-Branched Aldehydes

Syntheses and Synthetic Applications of Functionalized Propargylic and Allylic Fluorides

Molecular Structure Modulated Trap Distribution and Carrier Migration in Fluorinated Epoxy Resin

Contact Info

Product

Resources

About