Browse
Submit Data
Databases
API
Help

Dataset Information

28 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Direct Access to Substituted 4-CF3 ?-Lactams at the C-3 Position.

ABSTRACT: Mono- and disubstituted 4-CF3 ?-lactams at the C-3 position have been obtained stereoselectively under basic conditions. A wide range of function such as alcohols, alkyls, aryls, esters, and double and triple bonds have been introduced.

SUBMITTER: Skibinska M

PROVIDER: S-EPMC6691124 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Direct Access to Substituted 4-CF3 β-Lactams at the C-3 Position.

Skibińska Monika M Kaźmierczak Marcin M Milcent Thierry T Cytlak Tomasz T Koroniak Henryk H Crousse Benoit B

Frontiers in chemistry 20190806

Mono- and disubstituted 4-CF3 β-lactams at the C-3 position have been obtained stereoselectively under basic conditions. A wide range of function such as alcohols, alkyls, aryls, esters, and double and triple bonds have been introduced. ...[more]

PMID: 31448256

Similar Datasets

Enhanced Synthetic Access to Tris-CF3-Substituted Corroles.

Project description:Separate focus on the oligomerization and oxidative cyclization steps required for the synthesis of 5,10,15-tris(trifluoromethyl)corrole revealed [bis(trifluoroacetoxy)iodo]benzene (PIFA) as a superior alternative oxidant. Under optimized conditions, the pure free-base corrole was obtained with a 6-fold increase in chemical yield and an 11-fold rise in isolated material per synthesis. The corresponding gallium(III) and manganese(III) complexes were isolated by adding the appropriate metal salt prior to corrole purification.

| S-EPMC7187640 | biostudies-literature

Cross-dehydrogenative coupling enables enantioselective access to CF3-substituted all-carbon quaternary stereocenters.

Project description:A cross-dehydrogenative coupling strategy for enantioselective access to acyclic CF3-substituted all-carbon quaternary stereocenters has been established. By using catalytic DDQ with MnO2 as an inexpensive terminal oxidant, asymmetric cross coupling of racemic δ-CF3-substituted phenols with indoles proceeded smoothly, providing CF3-bearing all-carbon quaternary stereocenters with excellent chemo- and enantioselectivities. The generality of the strategy is further demonstrated by efficient construction of all-carbon quaternary stereocenters bearing other polyfluoroalkyl and perfluoroalkyl groups such as CF2Cl, C2F5, and C3F7.

| S-EPMC8157275 | biostudies-literature

Pd-Catalyzed Allylation of Imines to Access α-CF3-Substituted α-Amino Acid Derivatives.

Project description:We herein report a high yielding protocol for the direct α-allylation of easily accessible trifluoropyruvate-derived imines using Pd-catalysis. The reaction gives access to a variety of different α-allylated-α-CF3-amino acids in a straightforward manner, starting from commercially available trifluoropyruvate. We also provide a proof-of-concept for an enantioselective protocol (up to er = 75:25) by using chiral phosphane ligands.

| S-EPMC6887540 | biostudies-literature

Access to N-CF3 Formamides by Reduction of N-CF3 Carbamoyl Fluorides.

Project description:The departure into unknown chemical space is essential for the discovery of new properties and function. We herein report the first synthetic access to N-trifluoromethylated formamides. The method involves the reduction of bench-stable NCF3 carbamoyl fluorides and is characterized by operational simplicity and mildness, tolerating a broad range of functional groups as well as stereocenters. The newly made N-CF3 formamide motif proved to be highly robust and compatible with diverse chemical transformations, underscoring its potential as building block in complex functional molecules.

| S-EPMC10099374 | biostudies-literature

Photoinduced Trifluoromethylation with CF3Br as a Trifluoromethyl Source: Synthesis of α-CF3-Substituted Ketones.

Project description:An efficient and novel photoinduced trifluoromethylation employing CF3Br as a trifluoromethyl source is described. With commercially accessible fac-Ir(III)(ppy)3 as the catalyst, radical trifluoromethylation between O-silyl enol ether and CF3Br occurs successfully. This method provides various α-CF3-substituted ketones with a broad substrate scope in good yields under mild reaction conditions.

| S-EPMC9089747 | biostudies-literature

Iridium-Catalyzed C-H Borylation of CF3-Substituted Pyridines.

Project description:Iridium-catalyzed C-H borylation of CF3-substituted pyridines is described in this paper. The boronic ester group can be installed on the α, β, or γ position of pyridine by an appropriate substitution pattern. Sterically governed regioselectivity provides convenient access to a variety of CF3-substituted pyridylboronic esters. These catalytic C-H borylation reactions were carried out neatly without the use of any solvent. Several functional groups, such as halo, ester, alkoxy, amino, etc., are compatible with this methodology. These pyridylboronic esters are amenable to column chromatography and the products were isolated in good to excellent yields. α-Borylated pyridines, although isolated in good yields, do not have a long shelf life. The boronic ester derivatives of these CF3-substituted pyridines can serve as useful precursors in the synthesis regime.

| S-EPMC8992268 | biostudies-literature

Catalytic asymmetric synthesis of CF3-substituted tertiary propargylic alcohols via direct aldol reaction of α-N3 amide.

Project description:Organofluorine compounds are found in several important classes of chemicals, such as pharmaceuticals, agrochemicals, and functional materials. Chemists have been immensely interested in the development of methodologies for expeditious access to fluorine containing building blocks. In this study, we report a new method for the catalytic asymmetric synthesis of CF3-substituted tertiary propargylic alcohols with two contiguous stereogenic centers via the direct aldol reaction of an α-N3 amide to trifluoromethyl ketones. The key to the success of this method is the identification of a catalyst comprising Cu(ii)/chiral hydroxamic acid to promote the desired aldol reaction, constructing a tetrasubstituted carbon in a highly stereoselective fashion. Despite substantial prior advances in asymmetric catalysis, this class of catalysts has not been utilized for the formation of carbon-carbon bond-forming reactions. Our mechanistic study sheds light on the unique profile of this catalytic system, where the Cu(ii) complex plays a bifunctional role of serving as a Lewis acid and a Brønsted base. Furthermore, the densely functionalized aldol adducts undergo chemoselective transformations, affording a series of fluorine containing chiral building blocks with widespread application.

| S-EPMC5424470 | biostudies-literature

Nickel-Catalyzed Amidoalkylation Reaction of γ-Hydroxy Lactams: An Access to 3-Substituted Isoindolinones.

Project description:An efficient Ni(ClO4)2·6H2O-promoted amidoalkylation reaction for the synthesis of 3-substituted isoindolinones involving various γ-hydroxy lactams and nucleophiles has been successfully developed. The transformation proceeds with both carbon (ketones and arenes) and heteroatom (alcohols, thiols, and amines) nucleophiles and in both intermolecular and intramolecular manners. The prominent features of the present strategy are wide substrate scope, excellent group tolerability, and moderate to good yields (up to 96% yield). The present strategy is also characterized by remarkable superiority over the current synthetic methods. Furthermore, the reaction could be scaled up to the multigram scale.

| S-EPMC6868882 | biostudies-literature

Formation of synthetically relevant CF3-substituted phenonium ions in superacid media.

Project description:Predestined to be transient theoretical species, phenonium ions can now be considered as cationic intermediates of choice in organic synthesis. Here, we demonstrate that under non-nucleophilic and superacidic conditions, CF3-substituted phenonium ions can be generated to furnish original CF3-substituted dihydrostilbenes of interest.

| S-EPMC9036966 | biostudies-literature

The [3+2] Annulation of CF3-Ketimines by Re Catalysis: Access to CF3-Containing Amino Heterocycles and Polyamides.

Project description:Transition metal catalyzed [3 + 2] annulation of imines with double bonds via directed C-H activation offers a direct access to amino cyclic motifs. However, owing to weak coordination and steric hindrance, trifluoromethylated ketimines have been an unaddressed challenge for TM-catalyzed annulations. Here, a rhenium-catalyzed [3 + 2] annulation of trifluoromethylated ketimines with isocyanates via C(sp2)-H activation has been disclosed. This approach provides an efficient platform for rapid access to a privileged library of CF3-containing iminoisoindolinones and polyamides by utilizing challenging CF3-ketimines as the annulation component. The capability of gram scale synthesis, the post-functionalization of the cyclization adduct, the derivation of complex natural molecules and the facile synthesis of polyamides highlight a diversity of synthetic potential of the current methodology.

| S-EPMC7644752 | biostudies-literature