- Quinim: A New Ligand Scaffold Enables Nickel-Catalyzed Enantioselective Synthesis of α-Alkylated ?-Lactam
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Herein, we report a nickel-catalyzed reductive cross-coupling reaction of easily accessible 3-butenyl carbamoyl chloride with primary alkyl iodide to access the chiral α-alkylated pyrrolidinone with broad substrate scope and high enantiomeric excess. The current art of synthesis still remains challenging on the enantioselective α-monoalkylation of pyrrolidinones. The newly designed chiral 8-quinoline imidazoline ligand (Quinim) is crucial for maintaining the reactivity and enantioselectivity to ensure the reductive cyclization of monosubstituted alkenes for unprecedented synthesis of chiral non-aromatic heterocycles.
- Chen, Yifeng,Qu, Jingping,Wu, Xianqing
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supporting information
p. 15654 - 15660
(2020/10/18)
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- Nickel-Catalyzed Formal Aminocarbonylation of Unactivated Alkyl Iodides with Isocyanides
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Herein, we disclose a Ni-catalyzed formal aminocarbonylation of primary and secondary unactivated aliphatic iodides with isocyanides to afford alkyl amide, which proceeds via the selective monomigratory insertion of isocyanides with alkyl iodides, subsequent β-hydride elimination, and hydrolysis process. The reaction features wide functional group tolerance under mild conditions. Additionally, the selective, one-pot hydrolysis of reaction mixture under acid conditions allows for expedient synthesis of the corresponding alkyl carboxylic acid.
- Chen, Yifeng,Huang, Wenyi,Qu, Jingping,Shrestha, Mohini,Wang, Yun,Weng, Yangyang
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supporting information
p. 3245 - 3250
(2020/04/21)
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- Homogeneous catalysis, heterogeneous recycling: A new family of branched molecules with hydrocarbon or fluorocarbon chains for the Friedl?nder synthesis of quinoline under solvent-free conditions
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A new family of branched catalysts with hydrocarbon or fluorocarbon chains was used to catalyze Friedl?nder reaction between 2-aminoarylketones and α-methylene ketones under solvent-free conditions in good to excellent yields. The catalysts exhibit temperature-dependent solubility and such a thermomorphic character allows them to be recovered by filtration conveniently at room temperature and reused at least five times. To some extent, the branched catalysts with hydrocarbon chains are superior to those with fluorocarbon chains, as they are cheaper and more biodegradable.
- Fang, Lei,Yu, Jianjun,Liu, Ying,Wang, Anyin,Wang, Limin
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p. 11004 - 11009
(2014/01/06)
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- Pheromone synthesis. Part 249: Syntheses of methyl (R,E)-2,4,5- tetradecatrienoate and methyl (2E,4Z)-2,4-decadienoate, the pheromone components of the male dried bean beetle, Acanthoscelides obtectus (Say)
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The enantiomers of methyl (E)-2,4,5-tetradecatrienoate (1), a component of the male pheromone of Acanthoscelides obtectus, were synthesized from the enantiomers of 1-undecyn-3-ol (6), which were obtained via asymmetric acetylation of (±)-1-trimethylsilyl-1-undecyn-3-ol (4) with vinyl acetate as catalyzed by lipase PS (Amano). The ortho ester Claisen rearrangement of 6 with triethyl orthoacetate was the key-step to generate the chiral allenic system. A new synthesis of (±)-1 was also executed starting from (±)-6. Three different syntheses of methyl (2E,4Z)-2,4-decadienoate (2), another component of the male pheromone of A. obtectus, were achieved by means of either palladium-catalyzed Heck reaction or a Claisen and an Al 2O3 catalyzed thermal rearrangements.
- Mori, Kenji
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experimental part
p. 1936 - 1946
(2012/04/10)
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- Impact of fluorine substituents on the rates of nucleophilic aliphatic substitution and β-elimination
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A measure of the quantitative effect of proximate fluorine substituents on the rates of SN2 and E2 reactions has been obtained through a study mainly of reactions of fluorinated n-alkyl bromides with weak base, strong nucleophile azide ion and strong base/nucleophile methoxide ion in the protic solvent methanol and the aprotic solvent, DMSO. The order of reactivity for SN2 reactions of azide in methanol at 50 °C was found to be: n-alkyl-Br > n-alkyl-CHFBr > n-perfluoroalkyl-CH2CH 2Br n-perfluoroalkyl-CH2Br > n-alkyl-CF2Br. Approximate relative rates of reaction were: 1, 0.20, 0.12, 1 × 10 -4, -5. The order of reactivity for E2 reactions was found to be: n-perfluoroalkyl-CH2CH2Br n-alkyl-CF2Br > n-alkyl-CHFBr > n-alkyl-Br. The approximate relative rates for reaction of methoxide in methanol at 50 °C were: 1100, 4.4, 1.9, 1.
- Martinez, Henry,Rebeyrol, Adele,Nelms, Taylor B.,Dolbier Jr., William R.
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experimental part
p. 167 - 175
(2012/03/27)
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- H3PW12O40-[bmim][FeCl4]: A novel and green catalyst-medium system for microwave-promoted selective interconversion of alkoxymethyl ethers into their corresponding nitriles, bromides and iodides
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In the present work, the catalytic activity of 12-tungstophosphoric acid immobilized on [bmim][FeCl4] ionic liquid as a highly efficient and eco-friendly catalytic system for rapid and chemoselective direct conversion of MOM- or EOM-ethers into their corresponding nitriles, bromides and iodides under microwave irradiation is reported. In these reactions, the products are obtained in high yields. The catalyst exhibited remarkable reactivity and was reused several times.
- Mohammadpoor-Baltork, Iraj,Moghadam, Majid,Tangestaninejad, Shahram,Mirkhani, Valiolah,Mirjafari, Arsalan
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experimental part
p. 1468 - 1473
(2011/10/09)
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- Microwave-promoted, one-pot conversion of alkoxymethylated protected alcohols into their corresponding nitriles, bromides, and iodides using [bmim][InCl4] as a green catalyst
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The Lewis acid room temperature ionic liquid, [bmim][InCl4], was found to be an efficient and green catalyst for the highly chemoselective and one-pot conversion of MOM- or EOM-ethers into their corresponding nitriles, bromides, and iodides under microwave irradiation. The procedures are simple, rapid, and high yielding. The catalyst exhibited a remarkable reactivity and is reusable.
- Mirjafari, Arsalan,Mohammadpoor-Baltork, Iraj,Moghadam, Majid,Tangestaninejad, Shahram,Mirkhani, Valiollah,Khosropour, Ahmad Reza
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supporting information; experimental part
p. 3274 - 3276
(2010/07/18)
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- Simple synthesis of fresh alkyl iodides using alcohols and hydriodic acid
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A simple synthesis of fresh alkyl iodides using alcohols and hydriodic acid (HI) is reported. The alkyl iodides were obtained in quick and easy work-up with good to excellent yields (66-94%) and very high purities (97-99%). Freshly prepared iodomethane and 1-iodobutane were applied to synthesize biologically relevant 3,7-dimethyladenine and 9-butyladenine, which were characterized thoroughly using 1D and 2D NMR, individually.
- Klein, Suzane M.,Zhang, Cungen,Jiang, Yu Lin
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p. 2638 - 2641
(2008/09/19)
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- Silicaphosphine (Silphos): A filterable reagent for the conversion of alcohols and thiols to alkyl bromides and iodides
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Silicaphosphine (Silphos), [P(Cl)3-n(SiO2) n], as a new heterogeneous reagent is introduced. This reagent converts alcohols and thiols to their corresponding bromides and iodides in the presence of X2 (X=Br, I) in refluxing CH3CN in high to quantitative yields. Use of Silphos provides a highly practical method for the easy separation of the Silphos oxide byproduct by a simple filtration.
- Iranpoor, Nasser,Firouzabadi, Habib,Jamalian, Arezu,Kazemi, Foad
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p. 5699 - 5704
(2007/10/03)
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- Direct bromination and iodination of non-activated alkanes by hypohalite reagents
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The direct functionalisation of alkanes through bromination and iodination has been successfully achieved. The combination of stoichiometric mixtures of elemental halogen and sodium alkoxides leads to the formation of alkyl hypobromites and hypoiodites as reagents. The halogenation occurs without external photostimulation under thermal reaction conditions. Georg Thieme Verlag Stuttgart.
- Montoro, Raul,Wirth, Thomas
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p. 1473 - 1478
(2007/10/03)
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- Solvent-free conversion of alcohols into iodides with NaI supported on KSF clay
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A variety of allylic, benzylic, primary, and secondary saturated alcohols have been converted into the corresponding iodides using NaI supported on KSF clay. Selective conversion of allylic and benzylic alcohols in the presence of primary and secondary saturated alcohols has also been demonstrated. Copyright Taylor & Francis, Inc.
- Tajbakhsh, Mahmood,Hosseinzadeh, Rahman,Lasemi, Zahra,Rostami, Ali
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p. 2905 - 2911
(2007/10/03)
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- Selective iodination of alcohols with NaI/Amberlyst 15 in acetonitrile
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A simple and effective procedure for conversion of primary, secondary, allylic and benzylic alcohols into the corresponding iodides is described using NaI/Amberlyst 15 in acetonitrile at room temperature. Selective conversion of benzylic alcohols in the presence of saturated alcohols into the corresponding benzylic iodides is achieved under these conditions.
- Tajbakhsh, Mahmood,Hosseinzadeh, Rahman,Lasemi, Zahra
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p. 635 - 638
(2007/10/03)
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- Direct Iodination of Alkanes
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(Matrix presented) A cheap and efficient iodination of hydrocarbons can be achieved by generating tert-butyl hypoiodite from iodine and sodium tert-butoxide. The alkane is reactant and solvent, and this metal-free process provides a clean solution for their direct iodination.
- Montoro, Raul,Wirth, Thomas
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p. 4729 - 4731
(2007/10/03)
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- Ionic liquids as reagents and solvents in conjunction with microwave heating: Rapid synthesis of alkyl halides from alcohols and nitriles from aryl halides
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We show that using ionic liquids as reagents in conjunction with microwave heating it is possible to prepare primary alkyl halides from the corresponding alcohols rapidly. Using ionic liquids as solvents in conjunction with microwave heating it is possible to prepare aryl nitriles from the corresponding aryl bromides or iodides. The scope and limitations of using microwave-promotion as a tool in these reactions is discussed.
- Leadbeater, Nicholas E.,Torenius, Hanna M.,Tye, Heather
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p. 2253 - 2258
(2007/10/03)
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- A new direct homolytic iodination reaction of alkanes by perfluoroalkyl iodides
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A new method for the direct free-radical chain iodination of alkanes by perfluoroalkyl iodides is described.
- Liguori, Lucia,Bjorsvik, Hans-Rene,Bravo, Anna,Fontana, Francesca,Minisci, Francesco
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p. 1501 - 1502
(2007/10/03)
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- Halogen-exchange reactions between alkyl fluorides and boron trihalides or tetrahalides. A convenient synthesis of alkyl halides from alkyl fluorides
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A simple and effective method for converting fluoroalkanes to their corresponding chloro-, bromo- and iodo-alkanes using commercially available boron trihalides and titanium tetrahalides is described. - Keywords: Halogen-exchange reactions; Alkyl fluorides; Boron trihalides; Titanium tetrahalides; NMR spectroscopy; Mass spectrometry
- Namavari, Mohammad,Satyamurthy, N.,Barrio, Jorge R.
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- Hydroborations, reductions and reductive iodinations using BHI2:N(C2H5)2Ph complex
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The BHI2:N(C2H5)2Ph complex, prepared by the reaction of BH3:N(C2H5)2Ph with I2, is useful for hydroboration of alkenes, reduction of amides, iodination of alcohols, reductive iodination of carboxylic acids, aldehydes and ketones. Selective hydroboration of monosubstituted olefin over disubstituted olefinic moiety and terminal olefin over internal alkyne moiety have been achieved using this reagent. Carboxylic esters and nitriles are not affected by this reagent. Selective hydroboration of 1-alkenes and selective reductive iodination of cyclohexanone are achieved in the presence of ester and nitrile functional groups.
- Kishan Reddy,Periasamy
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p. 8329 - 8336
(2007/10/02)
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- Halogen exchange reactions between alkyl halides and aqueous hydrogen halides. A new method for preparation of alkyl halides
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Alkyl fluorides and chlorides are efficiently converted to their corresponding alkyl bromides and iodides by using readily available aqueous HBr and HI. The application of the same method for the conversion of some alkyl fluorides to the corresponding alkyl chlorides with cone. HCl is also described.
- Namavari, Mohammad,Satyamurthy,Phelps, Michael E.,Barrio, Jorge R.
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p. 4973 - 4976
(2007/10/02)
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- A Simple Convenient Procedure for Iodination of Alcohols and Reductive Iodination of Carbonyl Compounds using N,N-Diethylaniline-Borane-I2 system.
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Alcohols, carboxylic acids and carbonyl compounds give the corresponding alkyl iodides in moderate to good yields on reaction with N,N-diethylaniline-borane complex and iodine.
- Reddy, Ch. Kishan,Periasamy, M.
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p. 5663 - 5664
(2007/10/02)
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- Functionalized Ethylene Oligomers as Phase-Transfer Catalysts
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Ethylene oligomers with Mv in the range 1000-3000 containing terminal groups such as crown ethers, azacrown ethers, and phosphonium salts have been prepared and used as phase-transfer catalysts.These oligomeric catalysts have solubility properties similar to polyethylene in that they are insoluble at 25 deg C but dissolve in organic solutions at elevated (90-110 deg C) temperatures.Such oligomeric phase-transfer catalysts have activities comparable to their low molecular wait congeners and to activities reported for insoluble polystyrene-bound phase-transfer catalysts.After these oligomeric catalysts have been used in a reaction at 100 deg C, thay can be readily separated from the reaction products by cooling to form a precipitate, which can be isolated by filtration.Such catalysts may be reused without loss of activity.These catalysts are also effective in "solid-liquid" phase-transfer reactions in which an inorganic solid is suspended in a hot organic solution containing catalyst and substrate.
- Bergbreiter, David E.,Blanton, J. R.
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p. 5828 - 5833
(2007/10/02)
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- The efficiency of diphenylalkylsulfonium salts as alkylating agents
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A series of the title reagents have been used for the alkylation of a number of nucleophiles including iodide, cyanide, thiocyanate and fluoride ions as well as ethyl acetoacetate, phenylacetonitrile and a variety of nitrogen heterocyclic compounds.The results compared favorably with literature methods.
- Badet, Bernard,Julia, Marc,Lefebvre, Christian
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p. 431 - 434
(2007/10/02)
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- Effect of a Perfluoroalkyl Group on the Elimination and Substitution Reactions of Two Homologous Series of Perfluoroalkyl-Substituted Iodoalkanes
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Substitution and elimination reactions of two homologous series of compounds, induced by strong bases, were studied in aqueous alcohol and anhydrous methanol solution.Series I compounds, RF(CH2)nI having n = 2 (RF = a perfluoroalkyl group, also named an F-alkyl group), gave only RFCH=CH2 under all conditions.By contrast, RF(CH2)3Igave 4-10 times as much substitution as elimination products.Isomerization of RFCH2CH=CH2 (6) to RFCH=CHCH3 (7) occurred; this result may account, in part, for the extremely high 7/6 alkene ratios (37-81/1) obtained from elimination reactions of RFCH2CHICH3.All series II compounds, RFCH2CHI(CH2) nCH3 (n = 0-5), gave entirely elimination, and principally toward the RF group.E/Z isomer ratios varied from 2.65 to 5.These results were compared to those obtained from 1- and 2-iodooctane under the same conditions.A practical synthesis of CF3(CF2)5CH2CH2CH2I is described; the isomeric (F-alkyl)propenes 6 and 7 were also separately prepared.Rates of reactions under standard conditions for both series I and II compounds were measured.Kinetically, only second-order processes were observed, but a sharp break occurred in rate as the RF group was separated more than two carbons from the departing iodine atom, in series I compounds.Series II compounds reacted about one-tenth as fast as series I compounds.These results are discussed in the context of previous work with F-alkyl-substituted compounds.
- Brace, Neal O.,Marshall, Lawrence W.,Pinson, Carol J.,Wingerden, Gail van
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p. 2361 - 2368
(2007/10/02)
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- Formation of Iodides and Esters from Alcohols and Tributyldiiodophosphorane and Diiodotriphenylphosphorane
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Tributyldiiodophosphorane and diiodotriphenylphosphorane, prepared in situ from the corresponding phosphine and iodine, are generally able to convert primary and secondary alcohols into iodides at room temperature in diethyl ether or benzene containing two equivalents of hexamethylphosphoric triamide.Tertiary alcohols, as gauged by the lack of the reactivity of t-butyl alcohol, are, however, inert to this iodinating agents. 6-Hydroxyhexanoic acid yields a mixture of 6-iodohexanoic acid and 7-heptanolide.The first reagent also promotes facile condensation of secondaryand tertiary alcohols with carboxylic acids to form hindered esters in good yields.The phosphorane derived from tris(dimethylamino)phosphine and iodine, while less effective as an iodinating agent, rapidly converts 6-hydroxyhexanoic acid into 6-iodo-N,N-dimethylhexanamide, and hexanoic and benzoic acids into the corresponding N,N-dimethylamides in excellent yields at room temperature.Treatment of 3β-tosylocholest-5-ene with lithium iodide yields 3β-iodocholest-5-ene, and not 3α-iodocholest-5-ene, as previously reported.
- Haynes, Richard K.,Holden, Malcolm
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p. 517 - 524
(2007/10/02)
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