- Palladium-Catalyzed Aminocarbonylation of Aliphatic Alkenes with N,N-Dimethylformamide as an in Situ Source of CO
-
The palladium-catalyzed aminocarbonylation of aliphatic alkenes is presented for the first time without the need for external CO pressure. N,N-dimethylformamide (DMF) is used as an in situ source of both the required carbon monoxide and the amine substrate. The applied palladium catalytic system is well-known for a number of carbonylation reactions, including those with CO surrogates and tandem isomerizing carbonylations. The reaction pathway was investigated and proved to proceed by an acid-catalyzed DMF decomposition to CO and dimethyl amine with subsequent aminocarbonylation of the alkene. Pressure-versus-time curves gave more insight into the correlation between acid concentration and aminocarbonylation activity. Aliphatic alkenes (terminal and internal) are transformed, also in commercial glassware, into the corresponding linear N,N-dimethylamides with excellent selectivities. Hence, amide synthesis by aminocarbonylation moves closer to application in standard organic laboratories. Do-it-yourself CO production: The aminocarbonylation of alkenes for aliphatic amide synthesis is presented for the first time using N,N-dimethylamine as an in situ source of both, the required CO and dimethylamine. Excellent selectivities to the linear product are ensured by isomerizing carbonylation applying a [Pd]/1,2-DTBPMB system. 1,2-DTBPMB=1,2-bis((di-tert-butylphos- phino)methyl)benzene.
- Seidensticker, Thomas,Furst, Marc R. L.,Frauenlob, Robin,Vondran, Johanna,Paetzold, Eckhard,Kragl, Udo,Vorholt, Andreas J.
-
-
Read Online
- Deoxygenative hydroboration of primary, secondary, and tertiary amides: Catalyst-free synthesis of various substituted amines
-
Transformation of relatively less reactive functional groups under catalyst-free conditions is an interesting aspect and requires a typical protocol. Herein, we report the synthesis of various primary, secondary, and tertiary amines through hydroboration of amides using pinacolborane under catalyst-free and solvent-free conditions. The deoxygenative hydroboration of primary and secondary amides proceeded with excellent conversions. The comparatively less reactive tertiary amides were also converted to the corresponding N,N-diamines in moderate yields under catalyst-free conditions, although alcohols were obtained as a minor product.
- Yi, Jaeeun,Kim, Hyun Tae,Jaladi, Ashok Kumar,An, Duk Keun
-
supporting information
p. 129 - 132
(2021/11/17)
-
- Amine-boranes as Dual-Purpose Reagents for Direct Amidation of Carboxylic Acids
-
Amine-boranes serve as dual-purpose reagents for direct amidation, activating aliphatic and aromatic carboxylic acids and, subsequently, delivering amines to provide the corresponding amides in up to 99% yields. Delivery of gaseous or low-boiling amines as their borane complexes provides a major advantage over existing methodologies. Utilizing amine-boranes containing borane incompatible functionalities allows for the preparation of functionalized amides. An intermolecular mechanism proceeding through a triacyloxyborane-amine complex is proposed.
- Choudhary, Shivani,Hamann, Henry J.,Ramachandran, P. Veeraraghavan
-
supporting information
(2020/11/13)
-
- A highly efficient catalytic α-alkylation of unactivated amides using primary alcohols
-
The α-alkylation of unactivated amides with alcohols is described. Using a NCP-type pincer Ir complex as the precatalyst and KOtBu as the base, the reactions of secondary or tertiary acetamides with benzyl or nonbenzyl primary alcohols occur at 80 °C, furnishing the alkylation products in good yields. This method represents a practical and green means of α-alkylation of amides in a relatively mild, efficient, and selective manner with low catalyst loadings (0.5 mol %).
- Yao, Wubing,Ma, Xiaochen,Guo, Le,Jia, Xiangqing,Hu, Aiguo,Huang, Zheng
-
supporting information
p. 2919 - 2921
(2016/06/13)
-
- Ruthenium-catalyzed direct α-alkylation of amides using alcohols
-
The highly efficient direct α-alkylation of unactivated amides has been accomplished using alcohols in the presence of the Ru-PNN catalyst (0.1 mol%) with a high turnover number. Using this approach, 2-oxindole was directly transformed into C3-alkylated 3-hydroxyindolin-2-one in one step without the use of any oxidant.
- Chaudhari, Moreshwar Bhagwan,Bisht, Girish Singh,Kumari, Pooja,Gnanaprakasam, Boopathy
-
supporting information
p. 9215 - 9220
(2016/10/13)
-
- Catalytic Enantioselective α-Fluorination of 2-Acyl Imidazoles via Iridium Complexes
-
The first highly enantioselective α-fluorination of 2-acyl imidazoles utilizing iridium catalysis has been accomplished. This transformation features mild conditions and a remarkably broad substrate scope, providing an efficient and highly enantioselective approach to obtain a wide range of fluorine-containing 2-acyl imidazoles which are found in a variety of bioactive compounds and prodrugs. A large scale synthesis has also been tested to demonstrate the potential utility of this fluorination method.
- Xu, Guo-Qiang,Liang, Hui,Fang, Jie,Jia, Zhi-Long,Chen, Jian-Qiang,Xu, Peng-Fei
-
supporting information
p. 3355 - 3358
(2016/12/09)
-
- Iridium-catalyzed selective α-alkylation of unactivated amides with primary alcohols
-
The first α-alkylation of unactivated amides with primary alcohols is described. An effective and robust iridium pincer complex has been developed for selective α-alkylation of tertiary and secondary acetamides involving a borrowing hydrogen methodology. The method is compatible with alcohols bearing various functional groups. This presents a convenient and environmentally benign protocol for α-alkylation of amides.
- Guo, Le,Liu, Yinghua,Yao, Wubing,Leng, Xuebing,Huang, Zheng
-
supporting information
p. 1144 - 1147
(2013/04/10)
-
- Cyclopropylamines from N,N-dialkylcarboxamides and grignard reagents in the presence of titanium tetraisopropoxide or methyltitanium triisopropoxide
-
Thirty-three different N,N-dialkyl- and N-alkyl-N-phosphorylalkyl- substituted carboxamides 9-17 were treated with unsubstituted as well as with 2-alkyl-, 2,2-dialkyl-, and 3-alkenyl-substituted ethylmagnesium bromides 6 in the presence of stoichiometric amounts of titanium tetraisopropoxide or methyltitanium triisopropoxide to furnish substituted cyclopropylamines 20-25 in 20-98 % yield, depending on the substituents with no (1:1) to excellent (>25:1) diastereoselectivities. Generally higher yields (up to 98 %) of the cyclopropylamines 20-28 without loss of the diastereoselectivity were obtained with methyltitanium triisopropoxide as the titanium mediator. Under these conditions, even dioxolane-protected ketones and halogen-substituted and chiral as well as achiral alkyloxyalkyl-substituted carboxamides could be converted to the correspondingly substituted cyclopropylamines with unsubstituted as well as phenyl- and a variety of alkyl-substituted ethylmagnesium bromides in addition to numerous heteroatom-containing (e.g., halogen-, trityloxy-, tetrahydropyranyloxy-substituted) Grignard reagents (62 examples altogether). The transformation of N,N-diformylalkylamines 54 with ethylmagnesium bromide in the presence of methyltitanium triisopropoxide to N,N-dicyclopropyl-N- alkylamines 55 can be brought about in up to 82 % yield (6 examples). An asymmetric variant of the titanium-mediated cyclopropanation of N,N-dialkylcarboxamides has been developed by applying chiral titanium mediators generated from stoichiometric amounts of titanium tetraisopropoxide and chiral diamino or diol ligands, respectively. The most efficient chiral mediators turned out to be titanium bistaddolates that provided the corresponding cyclopropylamines with enantiomeric excesses (ee) of up to 84 %. Evaluation of several silyl-based additives revealed that the reaction can also efficiently be carried out with substoichiometric amounts (down to 25 Mol %) of the titanium reagent, as long as 2-aryl- or 2-ethenyl-substituted ethylmagnesium halides are used and a concomitant slight decrease in yields is accepted. The newly developed methodology was successfully applied for the preparation of analogues with cyclopropylamine moieties of known drugs and natural products such as the nicotine metabolite (S)-Cotinine as well as the insecticides Dinotefuran and Imidacloprid. Ti is it: Cyclopropylamines have been obtained in low to excellent yield through the reaction of different N,N-dialkyl- and N-alkyl-N- phosphorylalkyl-substituted carboxamides with Grignard reagents in the presence of stoichiometric amounts of titanium tetraisopropoxide or methyltitanium triisopropoxide (see scheme). Copyright
- De Meijere, Armin,Chaplinski, Vladimir,Winsel, Harald,Kordes, Markus,Stecker, Bjoern,Gazizova, Vesta,Savchenko, Andrei I.,Boese, Roland,Schill, Farina
-
supporting information; experimental part
p. 13862 - 13875
(2011/03/18)
-
- PROCESS FOR PRODUCING N,N-DIALKYL SUBSTITUTED FATTY ACIDS AMIDES
-
Disclosed herein is a process for producing Dialkyl substituted fatty acids amides. More particularly the present invention provides a process for producing pure form of N,N-dimethylamide of aliphatic carboxylic acids, wherein the aliphatic carboxylic acid is Octanoic Acid and Hexanoic Acid. The disclosed process comprises condensing Alkanoyl Chloride with dilute solution of Dialkylamine at a temperature of about 8 to 12°C and isolating the crude by salting out the reaction mixture employing Sodium Chloride and distilling the same under vacuum.
- -
-
Page/Page column 6
(2008/06/13)
-
- Some features of an SmI2-(Me2N)3P-THF system. Transformation of esters into dimethylamides
-
Sm11-intermediates generated upon addition of (Me2N)3P to a solution of SmI2 in THF exhibit the properties of a single-electron reducing agent and an N-nucleophile. In particular, N,N-dimethylamides are formed from esters.
- Ivanova,Shainurova,Miftakhov
-
p. 329 - 331
(2007/10/03)
-
- Chromium(ii)-mediated reactions of iodonium tetrafluoroborates with aldehydes: Umpolung of reactivity of diaryl-, alkenyl(aryl)-, and alkynyl(aryl)iodonium tetrafluoroborates
-
The method described herein allows us, for the first time, to perform umpolung of reactivity of diaryl-, alkenyl(aryl)-, and alkynyl(aryl)iodonium tetrafluoroborates. The method involves generation of organochromium(III) species via reaction of iodonium salts with anhydrous chromium dichloride, followed by their nucleophilic addition to aldehydes to yield alcohols. In contrast to the reaction of aryl and alkenyl halides with chromium dichloride, these iodonium salts are so active that organochromium(III) could be generated without using a nickel catalyst. Substituent effects of unsymmetrically substituted diaryliodonium salts on the product profiles are in good agreement with the reported mode of decomposition of the intermediate unsymmetrical diaryliodanyl radicals. Alkenyl(mesityl)iodonium tetrafluoroborates undergo exclusive alkenylation of aldehydes with no signs of the formation of an arylation product.
- Chen, Da-Wei,Ochiai, Masahito
-
p. 6804 - 6814
(2007/10/03)
-
- A New Versatile Reagent for the Synthesis of Cyclopropylamines Including 4-Azaspiro[2.n]alkanes and Bicyclo[n.1.0]alkylamines
-
The reaction of dialkylcarboxamides 1 with 1 equiv. of methyltriisopropyloxytitanium together with only 1.1 equiv. of a Grignard reagent gives cyclopropylamines 3 in better yields than the previously published method with 2 equiv. of Grignard reagent and 1 equiv. of Ti(OiPr)4. This new protocol can be applied to intramolecular reactions with in situ generation of the Grignard reagent from ω-bromo-N,N-dimethylhexanamide and methyl ω-bromohexanoate yielding the expected 1-dimethylaminocyclo[4.1.0]hexane 15 and the corresponding alcohol 18. Cyclohexylmagnesium bromide or chloride transforms N,N-dibenzylformamide and ethyl acetate to 7-exo-N,N-dibenzylaminonorcarane and 7-exo-hydroxy-7-methylnorcarane. N-Methyl-ε-caprolactam 25b and even the strained N-benzylpropiolactam 25a were converted to the spirocyclopropanated heterocycles 26a,b.
- Chaplinski, Vladimir,Winsel, Harald,Kordes, Markus,De Meijere, Armin
-
p. 111 - 114
(2007/10/03)
-
- Formation of Iodides and Esters from Alcohols and Tributyldiiodophosphorane and Diiodotriphenylphosphorane
-
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
-
p. 517 - 524
(2007/10/02)
-
