Accessing alkyl boronic esters via visible light-mediated decarboxylative addition reactions of redox-active esters

2020 ◽  
Vol 7 (15) ◽  
pp. 2003-2007
Author(s):  
Xianli Shu ◽  
Ruting Xu ◽  
Qiang Ma ◽  
Saihu Liao
Keyword(s):  
Carboxylic Acid ◽  
Visible Light ◽  
Addition Reaction ◽  
Addition Reactions ◽  
Active Esters ◽  
Redox Active ◽  
Boronic Esters

A visible light-mediated decarboxylative addition reaction for the synthesis of boronic esters based on abundant alkyl carboxylic acid feedstock has been developed.

scholarly journals Decarboxylative thiolation of redox-active esters to free thiols and further diversification

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Tianpeng Cao ◽  
Tianxiao Xu ◽  
Ruting Xu ◽  
Xianli Shu ◽  
Saihu Liao
Keyword(s):  
Natural Products ◽  
Carboxylic Acid ◽  
Visible Light ◽  
High Efficiency ◽  
Direct Access ◽  
Active Esters ◽  
Redox Active ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

Abstract Thiols are important precursors for the synthesis of a variety of pharmaceutically important sulfur-containing compounds. In view of the versatile reactivity of free thiols, here we report the development of a visible light-mediated direct decarboxylative thiolation reaction of alkyl redox-active esters to free thiols based on the abundant carboxylic acid feedstock. This transformation is applicable to various carboxylic acids, including primary, secondary, and tertiary acids as well as natural products and drugs, forging a general and facile access to free thiols with diverse structures. Moreover, the direct access to free thiols affords an advantage of rapid in situ diversification with high efficiency to other important thiol derivatives such as sulfide, disulfide, thiocyanide, thioselenide, etc.

Visible-Light-Induced Copper-Catalyzed Decarboxylative Coupling of Redox-Active Esters with N-Heteroarenes

2019 ◽  
Vol 21 (14) ◽  
pp. 5728-5732 ◽  
Author(s):  
Xue-Li Lyu ◽  
Shi-Sheng Huang ◽  
Hong-Jian Song ◽  
Yu-Xiu Liu ◽  
Qing-Min Wang
Keyword(s):  
Visible Light ◽  
Active Esters ◽  
Redox Active ◽  
Decarboxylative Coupling

Nucleophilic (Radio)Fluorination of Redox-Active Esters via Radical-Polar Crossover Enabled by Photoredox Catalysis

2020 ◽  
Author(s):  
Eric Webb ◽  
John Park ◽  
Erin L. Cole ◽  
David J. Donnelly ◽  
Samuel Bonacorsi, Jr. ◽  
...  
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Light Irradiation ◽  
Active Esters ◽  
Mild Conditions ◽  
Redox Active ◽  
Active Ester ◽  
Electron Transfers ◽  
Ester Substrate ◽  
Nucleophilic Fluorination

<p>We report a redox-neutral method for nucleophilic fluorination of N-hydroxyphthalimide esters using an Ir photocatalyst under visible light irradiation. The method provides access to a broad range of aliphatic fluorides, including primary, secondary, and tertiary benzylic fluorides as well as unactivated tertiary fluorides, that are typically inaccessible by nucleophilic fluorination due to competing elimination. In addition, we show that the decarboxylative fluorination conditions are readily adapted to radiofluorination with [<sup>18</sup>F]KF. We propose that the reactions proceed by two electron transfers between the Ir catalyst and redox-active ester substrate to afford a carbocation intermediate that undergoes subsequent trapping by fluoride. Examples of trapping with O- and C-centered nucleophiles and deoxyfluorination via N-hydroxyphthalimidoyl oxalates are also presented, suggesting that this approach may offer a general blueprint for affecting redox-neutral SN1 substitutions under mild conditions.</p>

Visible-light-induced iodine anion catalyzed decarboxylative/ deaminative C-H alkylation of enamides

2021 ◽  
Author(s):  
Jia-Xin Wang ◽  
Ya-Ting Wang ◽  
Hao Zhang ◽  
Ming-Chen Fu
Keyword(s):  
Amino Acid ◽  
Visible Light ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Active Esters ◽  
Cross Coupling Reactions ◽  
Redox Active ◽  
Iodine Anion

A visible-light-induced iodine anion catalyzed C-H stereoselective alkylation of enamides has been developed. Redox-active esters and Katritzky salts of the amino acid are amenable for decarboxylative/deaminative cross-coupling reactions, delivering various...

Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones

2017 ◽  
Vol 15 (29) ◽  
pp. 6089-6092 ◽  
Author(s):  
Feng Yin ◽  
Ainash Garifullina ◽  
Fujie Tanaka
Keyword(s):  
Carboxylic Acid ◽  
Michael Addition ◽  
Addition Reaction ◽  
Reaction System ◽  
Addition Reactions ◽  
Michael Addition Reaction ◽  
Asymmetric Michael Addition

An enantioselective Michael addition reaction system was developed. Using the reaction system, 5-methylpyrrolidine-3-carboxylic acid was synthesized in two steps.

Visible-light induced decarboxylative coupling of redox-active esters with disulfides to construct C–S bonds

2020 ◽  
Vol 56 (30) ◽  
pp. 4164-4167 ◽  
Author(s):  
Zhiwei Xiao ◽  
Lu Wang ◽  
Junjie Wei ◽  
Chongzhao Ran ◽  
Steven H. Liang ◽  
...  
Keyword(s):  
Visible Light ◽  
Active Esters ◽  
Redox Active ◽  
Decarboxylative Coupling ◽  
Novel Method

A novel method has been established for the construction of C–S bonds using redox-active esters with disulfides in the presence of Ru-photoredox catalyst.

scholarly journals Reductive coupling of imines with redox-active esters by visible light photoredox organocatalysis

2020 ◽  
Vol 7 (3) ◽  
pp. 602-608 ◽  
Author(s):  
Jiaqi Jia ◽  
Quentin Lefebvre ◽  
Magnus Rueping
Keyword(s):  
Visible Light ◽  
Bioactive Molecules ◽  
Secondary Amines ◽  
Reductive Coupling ◽  
Active Esters ◽  
Redox Active

The direct alkylation of imines with redox-active esters by visible light photoorganocatalysis provides a direct way for accessing α-branched secondary amines which are found in numerous bioactive molecules.

scholarly journals Nucleophilic (Radio)Fluorination of Redox-Active Esters via Radical-Polar Crossover Enabled by Photoredox Catalysis

2020 ◽  
Author(s):  
Eric Webb ◽  
John Park ◽  
Erin L. Cole ◽  
David J. Donnelly ◽  
Samuel Bonacorsi, Jr. ◽  
...  
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Light Irradiation ◽  
Active Esters ◽  
Mild Conditions ◽  
Redox Active ◽  
Active Ester ◽  
Electron Transfers ◽  
Ester Substrate ◽  
Nucleophilic Fluorination

<p>We report a redox-neutral method for nucleophilic fluorination of N-hydroxyphthalimide esters using an Ir photocatalyst under visible light irradiation. The method provides access to a broad range of aliphatic fluorides, including primary, secondary, and tertiary benzylic fluorides as well as unactivated tertiary fluorides, that are typically inaccessible by nucleophilic fluorination due to competing elimination. In addition, we show that the decarboxylative fluorination conditions are readily adapted to radiofluorination with [<sup>18</sup>F]KF. We propose that the reactions proceed by two electron transfers between the Ir catalyst and redox-active ester substrate to afford a carbocation intermediate that undergoes subsequent trapping by fluoride. Examples of trapping with O- and C-centered nucleophiles and deoxyfluorination via N-hydroxyphthalimidoyl oxalates are also presented, suggesting that this approach may offer a general blueprint for affecting redox-neutral SN1 substitutions under mild conditions.</p>

scholarly journals Recoverable Phospha-Michael Additions Catalyzed by a 4-N,N-Dimethylaminopyridinium Saccharinate Salt or a Fluorous Long-Chained Pyridine: Two Types of Reusable Base Catalysts

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1159
Author(s):  
Eskedar Tessema ◽  
Vijayanath Elakkat ◽  
Chiao-Fan Chiu ◽  
Jing-Hung Zheng ◽  
Ka Long Chan ◽  
...  
Keyword(s):  
Michael Addition ◽  
Polar Solvent ◽  
Addition Reaction ◽  
High Yield ◽  
Addition Reactions ◽  
Polar Solvents ◽  
Unsaturated Bond ◽  
Base Catalysts ◽  
Michael Additions

Phospha-Michael addition, which is the addition reaction of a phosphorus-based nucleophile to an acceptor-substituted unsaturated bond, certainly represents one of the most versatile and powerful tools for the formation of P-C bonds, since many different electrophiles and P nucleophiles can be combined with each other. This offers the possibility to access many diversely functionalized products. In this work, two kinds of basic pyridine-based organo-catalysts were used to efficiently catalyze phospha-Michael addition reactions, the 4-N,N-dimethylaminopyridinium saccharinate (DMAP·Hsac) salt and a fluorous long-chained pyridine (4-Rf-CH2OCH2-py, where Rf = C11F23). These catalysts have been synthesized and characterized by Lu’s group. The phospha-Michael addition of diisopropyl, dimethyl or triethyl phosphites to α, β-unsaturated malonates in the presence of those catalysts showed very good reactivity with high yield at 80–100 °C in 1–4.5 h with high catalytic recovery and reusability. With regard to significant catalytic recovery, sometimes more than eight cycles were observed for DMAP·Hsac adduct by using non-polar solvents (e.g., ether) to precipitate out the catalyst. In the case of the fluorous long-chained pyridine, the thermomorphic method was used to efficiently recover the catalyst for eight cycles in all the reactions. Thus, the easy separation of the catalysts from the products revealed the outstanding efficacy of our systems. To our knowledge, these are good examples of the application of recoverable organo-catalysts to the DMAP·Hsac adduct by using non-polar solvent and a fluorous long-chained pyridine under the thermomorphic mode in phospha-Michael addition reactions.

Sign in / Sign up

Export Citation Format

Share Document