- Photocatalytic Neophyl Rearrangement and Reduction of Distal Carbon Radicals by Iminyl Radical-Mediated C?C Bond Cleavage
-
The control of selectivity in the reactions of the highly reactive open-shell carbon radicals is an attractive but often challenging task. Building on the strategy of photoinduced iminyl radical-mediated C?C bond cleavage, we have developed photocatalytic neophyl rearrangement and reduction of distal carbon radicals under visible light irradiation of O-acyl oximes. This mild protocol tolerates a wide range of readily available O-acyl oximes, enabling facile synthesis of diversely substituted α,β-unsaturated nitriles and β-functionalized saturated nitriles in a highly selective manner. (Figure presented.).
- Yu, Xiao-Ye,Wang, Peng-Zi,Yan, Dong-Mei,Lu, Bin,Chen, Jia-Rong,Xiao, Wen-Jing
-
p. 3601 - 3606
(2018/09/18)
-
- One-Pot Preparation of C1-Homologated Aliphatic Nitriles from Aldehydes through a Wittig Reaction under Metal-Cyanide-Free Conditions
-
A one-pot protocol to obtain C1-homologated aliphatic nitriles was achieved by treating aromatic and aliphatic aldehydes with the (methoxymethyl)triphenylphosphonium ylide followed by hydrolysis of the resulting methyl vinyl ethers with pTsOH (Ts = para-toluenesulfonyl) and treatment with molecular iodine and aqueous ammonia under metal cyanide free conditions. Neopentyl-type nitriles, which could not be obtained by conventional methods that involved conversion of the neopentyl alcohol into a tosylate and treatment with metal cyanide, were successfully obtained by using the present method.
- Ezawa, Masatoshi,Togo, Hideo
-
p. 2379 - 2384
(2017/05/01)
-
- Conversion of 3,3,3-Trisubstituted Prop-1-ynes with tert-Butylhydrazine into 3,3,3-Trisubstituted Propionitriles Catalyzed by TpRh(C2H4)2/P(2-furyl)3
-
The combination of TpRh(C2H4)2 (Tp = tris(pyrazol-1-yl)borate) and P(2-furyl)3 catalyzes the reaction of tertiary alkyl-substituted alkynes with tert-butylhydrazine, leading to the formation of 3,3,3-trisubstituted propionitrile derivatives. This reaction system is applicable to 1,1-disubstituted propargyl alcohols and amines to afford the corresponding β-cyanohydrins and β-amino nitriles, respectively. The catalytic cycle involves the formation of a vinylidenerhodium complex as a key intermediate.
- Fukumoto, Yoshiya,Tamura, Yuto,Iyori, Yasuaki,Chatani, Naoto
-
p. 3161 - 3167
(2016/05/19)
-
- Photoinduced, Copper-Catalyzed Carbon-Carbon Bond Formation with Alkyl Electrophiles: Cyanation of Unactivated Secondary Alkyl Chlorides at Room Temperature
-
We have recently reported that, in the presence of light and a copper catalyst, nitrogen nucleophiles such as carbazoles and primary amides undergo C-N coupling with alkyl halides under mild conditions. In the present study, we establish that photoinduced, copper-catalyzed alkylation can also be applied to C-C bond formation, specifically, that the cyanation of unactivated secondary alkyl chlorides can be achieved at room temperature to afford nitriles, an important class of target molecules. Thus, in the presence of an inexpensive copper catalyst (CuI; no ligand coadditive) and a readily available light source (UVC compact fluorescent light bulb), a wide array of alkyl halides undergo cyanation in good yield. Our initial mechanistic studies are consistent with the hypothesis that an excited state of [Cu(CN)2]- may play a role, via single electron transfer, in this process. This investigation provides a rare example of a transition metal-catalyzed cyanation of an alkyl halide, as well as the first illustrations of photoinduced, copper-catalyzed alkylation with either a carbon nucleophile or a secondary alkyl chloride.
- Ratani, Tanvi S.,Bachman, Shoshana,Fu, Gregory C.,Peters, Jonas C.
-
supporting information
p. 13902 - 13907
(2016/01/15)
-
- PYRIMIDONE DERIVATIVES AND THEIR USE IN THE TREATMENT, AMELIORATION OR PREVENTION OF A VIRAL DISEASE
-
The present invention relates to a compound having the general formula (I), optionally in the form of a pharmaceutically acceptable salt, solvate, polymorph, codrug, cocrystal, prodrug, tautomer, racemate, enantiomer, or diastereomer or mixture thereof, which are useful in treating, ameloriating or preventing a viral disease. Furthermore, specific combination therapies are disclosed.
- -
-
-
- Iridium-catalyzed ring cleavage reaction of cyclobutanone O-benzoyloximes providing nitriles
-
(Chemical Equation Presented) Iridium-catalyzed ring cleavage reaction of cyclobutanone O-benzoyloximes in the presence of 9,10-dihydroanthracene and potassium carbonate proceeds to give saturated nitriles via C-C bond fission at the sterically more hinde
- Nishimura, Takahiro,Yoshinaka, Tomoaki,Nishiguchi, Yoshiki,Maeda, Yasunari,Uemura, Sakae
-
p. 2425 - 2427
(2007/10/03)
-
- Compounds that modulate PPAR activity and methods of preparation
-
This invention discloses compounds that alter PPAR activity. The invention also discloses pharmaceutically acceptable salts of the compounds, pharmaceutically acceptable compositions comprising the compounds or their salts, and methods of using them as therapeutic agents for treating or preventing hyperlipidemia and hypercholesteremia in a mammal. The present invention also discloses methods for making the disclosed compounds.
- -
-
-
- Azo derivatives of 5-aminosalicylic acid
-
Compounds of formula I and their salts and solvates are useful for the treatment or prevention of inflammatory bowel disease. Pharmaceutical compositions including these compounds and processes for their preparation are also provided. STR1
- -
-
-
- Piperidine derivatives with PAF antagonist activity
-
Compounds of general formula I and their salts and solvates are PAF antagonists and as such are useful in the treatment of various diseases or disorders mediated by PAF. Pharmaceutical compositions including these compounds and processes for their prepara
- -
-
-
- The Synthetic Potential of the Isocyanide-Cyanide Rearrangement
-
Excellent chemical and optical yields (>96percent retention) of cyanides are achieved by vapor phase thermolysis or short contact flow thermolysis of isocyanides. trans-2-Butenyl isocyanide rearranges without concomitant allylic isomerization to trans-2-butenyl cyanide.Optically active 1-(formyloxymethyl)-2-phenylethyl cyanide is obtained from optically active L-phenylalanine as a new type of chiral pool synthon.
- Meier, Michael,Ruechardt, Christoph
-
-
- The Isonitrile-Nitrile Rearrangement. A Reaction without a Structure-Reactivity Relationship
-
Reproducible rates of isomerisation of aliphatic isonitriles to nitriles in solution can be measured by GLC or IR when free-radical inhibitors are added to suppress a competing radical chain reaction.The reactivities of 19 primary, secondary, tertiary, cyclic, bicyclic, bridgehead, benzyl, substituted-benzyl, α-carbomethoxymethyl, and triphenylmethyl isocyanides in this rearrangement reaction vary by only a factor of 67 in rate or by +/- 2 kcal mol-1 in ΔG(excit.).This is explained by a tight hypervalent three-membered cyclic transition state in agreement with a previous prediction by ab initio calculation.The slower rate of 9-triptycyl isocyanide is proposed to be due to steric hindrance by the three peri hydrogens.Aromatic isocyanides isomerize about 10 times faster independent of polar para substituents and bulky ortho substituents.A hypervalent orthogonal transition state with retention of the aromatic sextet is proposed in contrast to the popular phenonium-type transition states for aryl migration in other 1,2-rearrangements.The reactivity data and the transition-state structures are discussed in context with other cationotropic 1,2-shifts.
- Meier, Michael,Mueller, Barbara,Ruechardt, Christoph
-
p. 648 - 652
(2007/10/02)
-