- Overcoming Selectivity Issues in Reversible Catalysis: A Transfer Hydrocyanation Exhibiting High Kinetic Control
-
Reversible catalytic reactions operate under thermodynamic control, and thus, establishing a selective catalytic system poses a considerable challenge. Herein, we report a reversible transfer hydrocyanation protocol that exhibits high selectivity for the thermodynamically less favorable branched isomer. Selectivity is achieved by exploiting the lower barrier for C-CN oxidative addition and reductive elimination at benzylic positions in the absence of a cocatalytic Lewis acid. Through the design of a novel type of HCN donor, a practical, branched-selective, HCN-free transfer hydrocyanation was realized. The synthetically useful resolution of a mixture of branched and linear nitrile isomers was also demonstrated to underline the value of reversible and selective transfer reactions. In a broader context, this work demonstrates that high kinetic selectivity can be achieved in reversible transfer reactions, thus opening new horizons for their synthetic applications.
- Bhawal, Benjamin N.,Ehinger, Christian,Morandi, Bill,Reisenbauer, Julia C.
-
supporting information
p. 10914 - 10920
(2020/07/13)
-
- Visible- And UV-Light-Induced Decarboxylative Radical Reactions of Benzoic Acids Using Organic Photoredox Catalysts
-
Photoinduced decarboxylative radical reactions of benzoic acids with electron-deficient alkenes, diborane, and acetonitrile under organic photoredox catalysis conditions and mild heating afforded adducts, arylboronate esters, and the reduction product, respectively. The reaction is thought to involve single-electron transfer promoted the generation of aryl radicals via decarboxylation. A diverse range of benzoic acids were found to be suitable substrates for this photoreaction. Only our two-molecule organic photoredox system can work well for the direct photoinduced decarboxylation of benzoic acids.
- Kubosaki, Suzuka,Takeuchi, Haruka,Iwata, Yutaka,Tanaka, Yosuke,Osaka, Kazuyuki,Yamawaki, Mugen,Morita, Toshio,Yoshimi, Yasuharu
-
p. 5362 - 5369
(2020/05/19)
-
- Cooperative Palladium/Lewis Acid-Catalyzed Transfer Hydrocyanation of Alkenes and Alkynes Using 1-Methylcyclohexa-2,5-diene-1-carbonitrile
-
Catalytic transfer hydrocyanation represents a clean and safe alternative to hydrocyanation processes using toxic HCN gas. Such reactions provide access to pharmaceutically important nitrile derivatives starting with alkenes and alkynes. Herein, an efficient and practical cooperative palladium/Lewis acid-catalyzed transfer hydrocyanation of alkenes and alkynes is presented using 1-methylcyclohexa-2,5-diene-1-carbonitrile as a benign and readily available HCN source. A large set of nitrile derivatives (>50 examples) are prepared from both aliphatic and aromatic alkenes with good to excellent anti-Markovnikov selectivity. A range of aliphatic alkenes engage in selective hydrocyanation to provide the corresponding nitriles. The introduced method is useful for chain walking hydrocyanation of internal alkenes to afford terminal nitriles in good regioselectivities. This protocol is also applicable to late-stage modification of bioactive molecules.
- Bhunia, Anup,Bergander, Klaus,Studer, Armido
-
supporting information
p. 16353 - 16359
(2018/11/25)
-
- A strategy for generating aryl radicals from arylborates through organic photoredox catalysis: Photo-Meerwein type arylation of electron-deficient alkenes
-
Photoinduced reactions of arylboronic acids with electron deficient alkenes under mild organic photoredox catalysis conditions lead to the formation of Meerwein arylation type adducts via the generation of aryl radicals.
- Iwata,Tanaka,Kubosaki,Morita,Yoshimi
-
supporting information
p. 1257 - 1260
(2018/02/09)
-
- Deboronative cyanation of potassium alkyltrifluoroborates: Via photoredox catalysis
-
A photoredox catalytic method was developed for the direct cyanation of alkyltrifluoroborates. This reaction provides a new and useful transformation of the easily available alkyltrifluoroborates. The photocatalytic reaction can tolerate a variety of functional groups with mild reaction conditions. Mechanistic investigations are consistent with the present reaction following a radical pathway.
- Dai, Jian-Jun,Zhang, Wen-Man,Shu, Yong-Jin,Sun, Yu-Yang,Xu, Jun,Feng, Yi-Si,Xu, Hua-Jian
-
p. 6793 - 6796
(2016/06/01)
-
- Synthesis of alkylated nitriles by [RuHCl(CO)(PPh3) 3]-catalyzed alkylation of acetonitrile using primary alcohols
-
Alkylation reaction of acetonitrile using primary alcohols is effectively catalyzed by [RuHCl(CO)(PPh3)3] in the presence of K 3PO4 as a base. Both benzylic and non-benzylic alcohols coupled with acetonitrile to give alkylated nitriles in good yields.
- Kuwahara, Takashi,Fukuyama, Takahide,Ryu, Ilhyong
-
supporting information
p. 1163 - 1165
(2013/10/22)
-
- Iridium-catalyzed α-alkylation of acetonitrile with primary and secondary alcohols
-
Acetonitrile is successfully alkylated with primary and secondary alcohols in the presence of t-BuOK using [Ir(OH)- (cod)]2 as a catalyst. This method provides a very clean and atom-economical convenient direct route to substituted nitriles, which are very important raw materials in organic and industrial chemistry.
- Sawaguchi, Takuya,Obora, Yasushi
-
supporting information; experimental part
p. 1055 - 1057
(2011/12/05)
-
- Guanidinium and Amidinium Fungicides: A New Class of Crbocation Mimetic Ergosterol Biosynthesis Inhibitors
-
A novel class of chemical has been designed with the aim of inhibiting the Δ14-reductase and Δ8-Δ7-isomerase enzymes in the ergosterol biosynthesis pathway in fungi. Use was made of knowledge about the mechanisms of both e
- Arnold, Mary L.,Duriatti, Albert D.,Jung, Michel,Katz, Ruth B.,Liebeschuetz, John W.
-
p. 341 - 356
(2007/10/03)
-