13048-17-4Relevant academic research and scientific papers
NON-AQUEOUS CYANATION OF HALIDES USING LITHIUM CYANIDE
Harusawa, Shinya,Yoneda, Ryuji,Omori, Yukie,Kurihara, Takushi
, p. 4189 - 4190 (1987)
Efficient conversion of various halides into the corresponding nitriles with lithium cyanide in tetrahydrofuran is described.
Lithium Cyanide Supported by O- and N-Donors
Budanow, Alexandra,Franz, Klaus-Dieter,Vitze, Hannes,Fink, Lothar,Alig, Edith,Bolte, Michael,Wagner, Matthias,Lerner, Hans-Wolfram
, p. 243 - 249 (2017)
A series of adducts of LiCN, namely [Li(Me2CO3)CN], [Li(Et2CO3)CN], and [Li(NMP)CN] (NMP = N-methyl-2-pyrrolidone) were prepared by treatment of solvent-free LiCN with the appropriate donor. The starting material for these approaches, donor-free LiCN, was quantitatively prepared from Me3SiCN and Li[Me] in diethyl ether at 0 °C. Alternatively, [Li(NMP)CN] was synthesized by metathesis reaction of LiCl with NaCN in the presence of stoichiometric amounts of NMP. Although [Li(Me2CO3)CN] and [Li(Et2CO3)CN] are water-sensitive compounds and decompose at the exposure to air, [Li(NMP)CN] is stable in air, even at elevated temperatures. The thermal stability of [Li(NMP)CN] was proven by differential thermal analysis (DTA). [Li(NMP)CN] shows thermal stability up to temperatures of about 132 °C. To evaluate the cyanation ability the reactions of 1-bromooctane and 3-bromocyclohexene with unsupported LiCN, [Li(NMP)CN], and a mixture of NaCN/LiCl/NMP were investigated. We found that [Li(NMP)CN] as well as LiCl/NaCN/NMP are efficient cyanation reagents comparable to the expensive and air-sensitive, donor-free LiCN. A product of the chloride-cyanide-bromide exchange could be isolated and structurally characterized by X-ray diffraction.
Michael addition of cyanide to cyclohex-1-enyliodonium salts
Fujita, Morifumi,Kim, Wan Hyeok,Okuyama, Tadashi
, p. 382 - 383 (2003)
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.
Electrophilic cyanation of allylic boranes: Synthesis of β,γ-unsaturated nitriles containing allylic quaternary carbon centers
Kiyokawa, Kensuke,Hata, Shotaro,Kainuma, Shunpei,Minakata, Satoshi
, p. 458 - 461 (2019/01/10)
The electrophilic cyanation of allylic boranes, a process that is applicable to the construction of allylic quaternary carbon centers, is reported. The reaction has a broad substrate scope with a high functional group tolerance. The results represent an u
(Guanidine)copper Complex-Catalyzed Enantioselective Dynamic Kinetic Allylic Alkynylation under Biphasic Condition
Cui, Xi-Yang,Ge, Yicen,Tan, Siu Min,Jiang, Huan,Tan, Davin,Lu, Yunpeng,Lee, Richmond,Tan, Choon-Hong
supporting information, p. 8448 - 8455 (2018/06/22)
Highly enantioselective allylic alkynylation of racemic bromides under biphasic condition is furnished in this report. This approach employs functionalized terminal alkynes as pro-nucleophiles and provides 6- and 7-membered cyclic 1,4-enynes with high yields and excellent enantioselectivities (up to 96% ee) under mild conditions. Enantioretentive derivatizations highlight the synthetic utility of this transformation. Cold-spray ionization mass spectrometry (CSI-MS) and X-ray crystallography were used to identify some catalytic intermediates, which include guanidinium cuprate ion pairs and a copper-alkynide complex. A linear correlation between the enantiopurity of the catalyst and reaction product indicates the presence of a copper complex bearing a single guanidine ligand at the enantio-determining step. Further experimental and computational studies supported that the alkynylation of allylic bromide underwent an anti-SN2′ pathway catalyzed by nucleophilic cuprate species. Moreover, metal-assisted racemization of allylic bromide allowed the reaction to proceed in a dynamic kinetic fashion to afford the major enantiomer in high yield.
Nickel(0)-catalyzed asymmetric hydrocyanation of 1,3-dienes
Saha, Biswajit,RajanBabu
, p. 4657 - 4659 (2007/10/03)
1,2-Bis-diarylphosphinites are excellent ligands for the Ni(0)-catalyzed hydrocyanation of certain types of 1,3-dienes. 1-Phenyl-1,3-butadiene, 1-vinyl-3,4-dihydronaphthalene, and 1-vinylindene undergo highly regioselective hydrocyanation under ambient co
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.
(2-hydroxy)ethyl-thioureas useful as modulators of alpha2B adrenergic receptors
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, (2008/06/13)
Compounds of formula (i) and of formula (ii) wherein the symbols have the meaning disclosed in the specification, specifically or selectively modulate α2B and/or α2C adrenergic receptors in preference over α2A adrenergic receptors, and as such are useful for alleviating chronic pain and allodynia and have no or only minimal cardivascular and/or sedatory activity.
Stereoselective synthesis of a conformationally defined cyclohexyl carnitine analogue that binds CPT-1 with high affinity
Hutchison, Tracy L.,Saeed, Ashraf,Wolkowicz, Paul E.,McMillin, Jeanie B.,Brouillette, Wayne J.
, p. 1505 - 1511 (2007/10/03)
Carnitine (1, 3-hydroxy-4-trimethylammoniobutyrate) is important in mammalian tissue as a carrier of acyl groups. In order to explore the binding requirements of the carnitine acyltransferases for carnitine, we designed conformationally defined cy- clohexyl carnitine analogues. These diastereomers contain the required gauche conformation between the trimethylammonium and hydroxy groups but vary the conformation between the hydroxy and carboxylic acid groups. Here we describe the synthesis and biological activity of the all-trans diastereomer (2), which was prepared by the ring opening of trans-methyl 2,3-epoxycylohex- anecarboxylate with NaN3 . Racemic 2 was a competitive inhibitor of neonatal rat cardiac myocyte CPT-1 (K(i) 0.5 mMfor racemic 2; K(m) 0.2 mM for L-carnitine) and a noncompetitive inhibitor of neonatal rat cardiac myocyte CPT-2 (K(i) 0.67 mM). These results suggest that 2 represents the bound conformation of carnitine for CPT-1. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.
Diastereoselectivity in the epoxidation of substituted cyclohexenes by dimethyldioxirane
Murray, Robert W.,Singh, Megh,Williams, Brian L.,Moncrieff, Hazel M.
, p. 1830 - 1841 (2007/10/03)
Three series of compounds based on the cyclohexene framework have been epoxidized by dimetbyldioxirane. A pronounced dependence of epoxide diastereoselectivity on substituent has been observed. In addition there is a solvent influence on this stereoselectivity. The results have been explained by invoking steric, H-bonding, and dipole - dipole influences on the epoxide stereochemistry.
