18300-91-9Relevant academic research and scientific papers
Method for preparing nitrile by reacting acetone cyanohydrin with haloalkane
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Paragraph 0043-0049; 0051-0057; 0070, (2019/08/20)
The invention provides a method for preparing nitrile by reacting acetone cyanohydrin with haloalkane. According to the invention, by using acetone cyanohydrin as a cyaniding reagent, the problems, such as long reaction time, low yield, strict reaction conditions and the like enchanted in an existing preparation method in which highly toxic sodium cyanide or potassium cyanide or expensive trimethylsilyl cyanide is used as a cyanogen source, are solved. The method comprises the following steps: dissolving acetone cyanohydrin in a mixed solvent of a high boiling point dipolar aprotic solvent anda low boiling point aprotic solvent, adding a catalyst lithium hydroxide, stirring at 25-50 DEG C for one hour and then adding a haloalkane for continuous reaction for 2-3 hours; next, adding saturated saline water for washing twice, separating out an organic layer, and boiling off the solvent after drying, thereby obtaining a nitrile compound. The method for preparing a nitrile compound disclosed in the invention is characterized by low reaction toxicity, simple process, easy of operation, low production cost, and a yield of more than 95%.
Iron-catalyzed AlkylAlkyl negishi coupling of organoaluminum reagents
Agata, Ryosuke,Kawamura, Shintaro,Isozaki, Katsuhiro,Nakamura, Masaharu
supporting information, p. 238 - 241 (2019/03/13)
The first iron-catalyzed cross-coupling reaction of alkyl halides with alkylaluminum reagents (alkylalkyl Negishi coupling) is developed using an iron/bisphosphine catalyst system. The reaction shows high functional group tolerance: various primary alkyl halides possessing a non-protected indole, carboxyl, or hydroxy group are coupled with primary alkylaluminum reagents in good yields. Potassium fluoride plays a key role to promote the reaction by generating an aluminate species, which facilitates the transmetalation between the organoaluminum and the iron catalyst.
Thiol-Catalyzed Radical Decyanation of Aliphatic Nitriles with Sodium Borohydride
Kawamoto, Takuji,Oritani, Kyohei,Curran, Dennis P.,Kamimura, Akio
supporting information, p. 2084 - 2087 (2018/04/16)
Radical decyanation of aliphatic nitriles was achieved in the presence of NaBH4 and a thiol. The reaction proceeds via a radical mechanism involving borane radical anion addition to nitrile to form an iminyl radical, which undergoes carbon-carbon cleavage. Reductive radical addition to acrylonitrile is followed by decyanation to give a two-carbon homologated product in a net radical ethylation reaction.
Indium(III) acetate-catalyzed intermolecular radical addition of organic iodides to electron-deficient alkenes
Miura, Katsukiyo,Tomita, Mitsuru,Ichikawa, Junji,Hosomi, Akira
, p. 133 - 136 (2008/09/16)
In the presence of phenylsilane and a catalytic amount of indium(III) acetate, organic iodides added to electron-deficient alkenes in ethanol at room temperature. Both simple and functionalized organic iodides were applicable to this reaction. A plausible reaction mechanism involves the formation of indium hydride species by hydride transfer from silicon to indium and an indium hydride-mediated radical chain process.
Synthetic radical reactions using dibutylchlorogermane and dibutylethoxygermane as radical mediators
Miura, Katsukiyo,Ootsuka, Kazunori,Hosomi, Akira
, p. 3151 - 3153 (2007/10/03)
In the presence of Et3B as radical initiator, dibutylchlorogermane (1a) and dibutylethoxygermane (1b) reacted with bromo- and iodoalkanes at room temperature to give the corresponding alkanes in high yields. Hydrogermane 1a was more reactive than 1b. However, 1b worked as a better radical mediator in intermolecular radical addition of haloalkanes to electron-deficient alkenes. Georg Thieme Verlag Stuttgart.
Effect of heteroatom insertion at the side chain of 5-alkyl-1H-tetrazoles on their properties as catalysts for ester hydrolysis at neutral pH
Bhattacharya, Santanu,Vemula, Praveen Kumar
, p. 9677 - 9685 (2007/10/03)
Herein we introduce tetrazole and its suitably designed derivatives as powerful ester-cleaving reagents. By first performing a detailed ab initio computational study, we found that, in the side chain of 5-alkyl-1H-tetrazoles, introduction of a heteroatom (e.g., N, O, or S at the α-position of the tetrazole ring) raises the charge on the tetrazole nucleus significantly. All calculations have been performed using restricted Hartree-Fock (RHF) and hybrid ab initio/DFT (B3LYP) methods employing 6-31G* and 6-31+G* basis sets. To estimate the nucleophilicity of these reagents, the charges on conjugate bases of various tetrazole derivatives have been calculated using natural population (NBO) analysis in gas phase and in water. Free energy of protonation (fep) of the 1H-tetrazole derivatives (1-7), free energy of solvation, ΔGaq, and the corresponding pKa values have been calculated by self-consistent reaction field (SCRF) methods applying the polarized continuum model (PCM). Since the calculation indicates that incorporation of heteroatom leads to enhanced nucleophilicity in their deprotonated anionic tetrazole forms, a series of 5-substituted 1H-tetrazole derivatives have been synthesized. These compounds indeed catalyze the hydrolysis of p-nitrophenyl diphenyl phosphate (PNPDPP) and p-nitrophenyl hexanoate (PNPH) efficiently in cationic cetyl trimethylammonium bromide (CTABr) micelles at pH 7.0 and 25 °C. The pseudo-first-order rate constants (k obs) were determined for each catalyst against both substrates. The experimental and theoretical results show that, to achieve better k obs values for the cleavage of PNPDPP and PNPH under micellar conditions, charge on the N- atom (nucleophile) of conjugate base is important. Replacing the α-CH2 in alkyl substituent with S (3), NH (4), or O (5) enhances the accumulation of charge on N- in conjugate bases of tetrazoles and subsequently increases their intrinsic nucleophilic reactivity toward hydrolytic reactions. Significantly large rate enhancements were observed for the cleavage of PNPDPP and PNPH at pH 7.0 in the presence of catalytic system 5/CTABr over background (only CTABr). Tetrazole 4 (α-isomer) showed 4-5-fold superior reactivity over 6 (β-isomer) under identical conditions. Natural charges obtained from NBO analysis (B3LYP/ 6-31+G*) are -0.94 and -0.852 on N- in the conjugate bases of 4 and 6, respectively. This also predicts that 4 is a better nucleophile than 6. All the newly synthesized tetrazole derivatives in micellar media display true catalytic properties by cleaving several fold excess of substrates.
A method for palladium-catalyzed cross-couplings of simple alkyl chlorides: Suzuki reactions catalyzed by [Pd2(dba)3]/PCy3
Kirchhoff, Jan H.,Dai, Chaoyang,Fu, Gregory C.
, p. 1945 - 1947 (2007/10/03)
The window of reactivity is relatively narrow in the first Suzuki cross-coupling of alkyl chlorides with alkyl 9-borabicyclo[3.3.1]nonane (9-BBN) derivatives catalyzed by [Pd2(dba)3] [Eq. (1); dba = (E,E)-dibenzylideneacetone]: whereas good yields are obtained with the ligand tricyclohexylphosphane for ligands that are appreciably larger or smaller, essentially no coupling is observed. As the conditions are compatible with a variety of functional groups, this method introduces a new class of substrates into the family of potential partners in palladium-catalyzed cross-coupling reactions.
Radical reaction by a combination of phosphinic acid and a base in aqueous media
Yorimitsu,Shinokubo,Oshima
, p. 225 - 235 (2007/10/03)
Treatment of various organic halides with phosphinic acid (hypophosphorous acid) in aqueous ethanol in the presence of a radical initiator and a base gave the corresponding reduced products in high yields. Addition of a base is indispensable for the reduction of halides by phosphinic acid. Allylic ether of o-iodophenol or 2-haloalkanal allylic acetal underwent radical cyclization under the same conditions to afford the corresponding cyclic product in excellent yield. Deuterated phosphinic acid was found to be an efficient chain carrier for the radical deuteration of organic halides. For example, a deuterium oxide solution of deuterated phosphinic acid, potassium carbonate, 2,2′-azobis(isobutyramidine) dihydrochloride as an initiator, and p-iodobenzoic acid was heated at reflux to give p-deuteriobenzoic acid in 94% yield. A mixed dioxane/D2O solvent system combined with DBU and potassium peroxodisulfate was crucial to deuterate hydrophobic substrates in high yields and with high deuterium incorporation. Complete deuterium incorporation was accomplished only by the reaction in D2O without an organic cosolvent and an organic base.
A New and Efficient Synthesis of Trifluoromethyl Ketones from Carboxylic Acids. Part I.
Boivin, Jean,El Kaim, Laurent,Zard, Samir Z.
, p. 2573 - 2584 (2007/10/02)
Trifluoromethyl ketones can be prepared in good yield from primary carboxylic acid chlorides by reaction with pyridine and trifluoroacetic anhydride followed by aqueous work up.
A SIMPLE ONE-POT SYNTHESIS OF NITRILES FROM ALCOHOLS
Camps, F.,Gasol, V.,Guerrero, A.
, p. 445 - 452 (2007/10/02)
Primary alcohols are cleanly converted into nitriles in excellent yields by a new, one-pot, two-step process, involving transformation into the corresponding trifluoroacetates followed by nucleophilic substitution reaction with sodium cyanide.
