628-02-4Relevant articles and documents
Conversion of Aliphatic Amides into Amines with benzene. 2. Kinetics and Mechanism
Boutin, Raymond H.,Loudon, G. Marc
, p. 4277 - 4284 (1984)
The reagent benzene (PIFA), used to prepare amines from amides as described in the preceding paper, dissolves in 50:50 (v/v) aqueous acetonitrile to give an acidic solution.This behavior can be explained quantitatively by the dimerization of PIFA in solution under preparatively significant conditions; the dimer, μ-oxo-I,I'-bis(trifluoroacetato-O)-I,I'-diphenyldiiodine(III), 2, can be isolated from the reaction mixture above pH 3.The rate of hexanamide rearrangement by PIFA was studied as a function of PIFA concentration and shown to display asymtotic behavior.The rate is depressed by added trifluoroacetate and accelerated by increasing pH, but not in a simple way.These observations can be accounted for by a mechanism (eq 13-15) in which the dimer 2 complexes with the amide, releasing acid.It is this released acid that accounts for most of the kinetically significant observations.The rearrangement of the amide-dimer complex is the rate-limiting step.Other kinetically indistinguishable mechanism are also possible.The rate of rearrangement promoted by dimer alone is in agreement with that predicted by the proposed mechanism.The imidic acid (enol) form of the amide is considered as a possible kinetically active form of the amide but is rejected on kinetic grounds.
Deoxygenative hydroboration of primary, secondary, and tertiary amides: Catalyst-free synthesis of various substituted amines
An, Duk Keun,Jaladi, Ashok Kumar,Kim, Hyun Tae,Yi, Jaeeun
supporting information, (2021/11/17)
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.
Efficient heterogeneous hydroaminocarbonylation of olefins with ammonium chloride as amino source
Sun, Zhao,Yan, Li,Ji, Guangjun,Wang, Guoqing,Ma, Lei,Jiang, Miao,Li, Cunyao,Ding, Yunjie
, (2021/02/26)
An efficient protocol for heterogeneous hydroaminocarbonylation of olefins with ammonium chloride without addition of acid additive has been developed for the first time. We successfully synthesized the Pd@POPs-PPh3 catalyst through a solvothermal synthetic method. Under this heterogeneous catalytic system, C2-C6 olefins displayed good yields and TON, and a yield of 66% of propionamide and TON = 1400 were obtained under mild reaction conditions (403 K, Pethylene = 0.5 MPa, PCO = 2.5 MPa), which is a little higher than those in the homogeneous system. This catalytic system has the advantage of easy separation of product and catalyst, as well as good stability. Uniform dispersion of Pd active sites, strong coordination bond between P and Pd, high surface area, large pore volume and hierarchical porosity of Pd@POPs-PPh3 were confirmed by a series of characterizations, which is believed to be the keys for the good activity and stability of hydroaminocarbonylation reaction.
Amine-boranes as Dual-Purpose Reagents for Direct Amidation of Carboxylic Acids
Choudhary, Shivani,Hamann, Henry J.,Ramachandran, P. Veeraraghavan
supporting information, (2020/11/13)
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.
