1855-63-6Relevant articles and documents
A New Preparative Method for α,β-Unsaturated Nitriles by the Palladium-catalysed Decarboxylation-Dehydrogenation of Allyl α-Cyanocarboxylates
Minami, Ichiro,Yuhara, Masami,Shimizu, Isao,Tsuji, Jiro
, p. 118 - 119 (1986)
Allyl α-cyanocarboxylates, derived from cyanoacetic acid, were converted into α,β-unsaturated nitriles in the presence of a palladium catalyst.
Cyanation of 1-Halocycloalkenes Catalyzed by Tetracyanocobaltate(I). Convenient Synthesis of 1-Cyanocycloalkenes
Funabiki, Takuzo,Kishi, Hirohito,Sato, Yoshihiro,Yoshida, Satohiro
, p. 649 - 650 (1983)
1-Cyanocycloalkenes (1-cyanocyclopentene, -hexene, -heptene, and -octene) were readily synthesized by catalytic cyanation of the corresponding 1-halocycloalkenes with tetracyanocobaltate(I).Reactivities of methyl-substituted 1-chlorocyclohexenes were lower than that of 1-chlorocyclohexene, and 1-chloro-2-methylcyclohexene scarecely reacted.Hydrogenation and isomerization of 1-cyanocycloalkenes were observed only with 1-cyanocycloheptene and 1-cyano-6-methylcyclohexene, respectively.
Amide α,β-Dehydrogenation Using Allyl-Palladium Catalysis and a Hindered Monodentate Anilide
Chen, Yifeng,Turlik, Aneta,Newhouse, Timothy R.
supporting information, p. 1166 - 1169 (2016/02/18)
A practical and direct method for the α,β-dehydrogenation of amides is reported using allyl-palladium catalysis. Critical to the success of this process was the synthesis and application of a novel lithium N-cyclohexyl anilide (LiCyan). The reaction conditions tolerate a wide variety of substrates, including those with acidic heteroatom nucleophiles.
Palladium-Catalyzed α,β-Dehydrogenation of Esters and Nitriles
Chen, Yifeng,Romaire, Justin P.,Newhouse, Timothy R.
supporting information, p. 5875 - 5878 (2015/05/27)
A highly practical and general palladium-catalyzed methodology for the α,β-dehydrogenation of esters and nitriles is reported. Generation of a zinc enolate or (cyanoalkyl)zinc species followed by the addition of an allyl oxidant and a palladium catalyst results in synthetically useful yields of α,β-unsaturated esters, lactones, and nitriles. Preliminary mechanistic investigations are consistent with reversible β-hydride elimination and turnover-limiting, propene-forming reductive elimination.
A chemoenzymatic synthesis of an androgen receptor antagonist
Vaidyanathan, Rajappa,Hesmondhalgh, Lynsey,Hu, Shanghui
, p. 903 - 906 (2012/12/30)
A new scalable enzymatic resolution approach to both enantiomers of trans-2-hydroxycyclohexanecarbonitrile (9 and 11) was developed. Treatment of the racemic mixture (4) with succinic anhydride in the presence of Novozym 435 led to selective acylation of one enantiomer to the corresponding hemisuccinate, which was separated from the unreacted enantiomer by a simple basic extraction. This procedure produced the desired enantiomer in high ee, while obviating the need for chromatography or expensive catalysts and ligands. The application of this protocol to the large-scale synthesis of an androgen receptor antagonist (1) is described.
Tandem alkylation-cyclization process via an O,C-dianion
Banaag, April R.,Berger, Gideon O.,Dhoro, Francis,Delos Santos, Derrick B.,Dixon, Darryl D.,Mitchell, James P.,Tokeshi, Bradley K.,Tius, Marcus A.
, p. 3419 - 3428 (2007/10/03)
A general protocol for preparing densely functionalized cyclopentenones through a tandem nucleophilic addition-deprotonation-alkylation-cyclization process is described. Addition of lithioallene 2 to enamides 1 generates tetrahedral intermediate 3. Deprotonation of the γ carbon atom of the allene function in situ, followed by trapping by a suitable electrophile and cyclization during workup leads to C6 substituted cyclopentenones 6.
Michael addition-elimination mechanism for nucleophilic substitution reaction of cycloalkenyl iodonium salts and selectivity of 1,2-hydrogen shift in cycloalkylidene intermediate
Fujita, Morifumi,Wan, Hyeok Kim,Fujiwara, Koji,Okuyama, Tadashi
, p. 480 - 488 (2007/10/03)
(Chemical Equation Presented) Reactions of cyclohexenyl and cyclopentenyl iodonium salts with cyanide ion in chloroform give cyanide substitution products of allylic and vinylic forms. Deuterium-labeling experiments show that the allylic product is formed via the Michael addition of cyanide to the vinylic iodonium salt, followed by elimination of the iodonio group and 1,2-hydrogen shift in the 2-cyanocycloalkylidene intermediate. The hydrogen shift preferentially occurs from the methylene rather than the methine β-position of the carbene, and the selectivity is rationalized by the DFT calculations. The Michael reaction was also observed in the reaction of cyclopentenyliodonium salt with acetate ion in chloroform. The vinylic substitution products are ascribed to the ligand-coupling (via λ3-iodane) and elimination-addition (via cyclohexyne) pathways.
Michael addition of cyanide to cyclohex-1-enyliodonium salts
Fujita, Morifumi,Kim, Wan Hyeok,Okuyama, Tadashi
, p. 382 - 383 (2007/10/03)
Reaction of 4-substituted cyclohex-1-enyliodonium salt with cyanide in chloroform produces three isomeric cyanocyclohexenes, ipso and two cine products. Deuterium labeling experiments showed that the allylic cine product is formed via the Michael addition of cyanide, followed by elimination of the iodonio group and a 1,2-H shift.
A convenient and stereoselective synthesis of alk-2-enenitriles
Dybowski, Piotr,Skowrońska, Aleksandra
, p. 284 - 286 (2007/10/03)
A convenient and stereoselective synthesis of alk-2-enenitriles based on the reaction of readily available S-(β-oxoalkyl)thiophosphates and Se-(β-oxoalkyl)selenophosphates with potassium cyanide in the presence of 18-crown-6 is described.
A new conversion of primary nitro compounds into nitriles
El Kaim, Laurent,Gacon, Ariane
, p. 3391 - 3394 (2007/10/03)
The reaction of primary nitro compounds with isocyanides and isocyanates in the presence of a base leads to a new preparation of nitriles. The reaction probably proceeds through the in situ formation of a nitrile oxide followed by a fast oxygen transfer with the isocyanide. Combined with the Knovenagel addition of nitromethane to cyclic ketone, this reaction brings a highly effective regioselective formation of cyclic α-β unsaturated nitriles.
