5498-74-8Relevant articles and documents
Photocatalyzed Multiple Additions of Amines to α,β-Unsaturated Esters and Nitriles
Das, Suresh,Kumar, J. S. Dileep,Thomas, K. George,Shivaramayya, K.,George, M. V.
, p. 628 - 634 (1994)
Photoelectron-transfer-catalyzed intermolecular carbon-carbon bond formation of primary, secondary, and tertiary amines with α,β-unsaturated esters and nitriles using photosensitizers such as anthraquinone, acridone, and dicyanoanthracene has been investigated.The addition of α-aminoalkyl radicals, generated via photoelectron-transfer processes, to olefinic substrates and the subsequent 1,5-hydrogen abstraction reactions of the amine-olefin adduct radicals lead to a number of interesting multiple-olefin-added products.The adducts of the primary and secondary amines with α,β-unsaturated esters undergo further cyclizations to give spiro and cyclic lactams, respectively.
Photocatalytic α-Tertiary Amine Synthesis via C?H Alkylation of Unmasked Primary Amines
Alder, Catherine M.,Ballantyne, George,Cresswell, Alexander J.,Cunningham, William B.,Edwards, Lee J.,Grayson, Matthew N.,Kinsella, Anna G.,McKay, Blandine S. J.,Mules, Tom,Ryder, Alison S. H.,Turner-Dore, Jacob
, p. 14986 - 14991 (2020/06/20)
A practical, catalytic entry to α,α,α-trisubstituted (α-tertiary) primary amines by C?H functionalisation has long been recognised as a critical gap in the synthetic toolbox. We report a simple and scalable solution to this problem that does not require any in situ protection of the amino group and proceeds with 100 percent atom-economy. Our strategy, which uses an organic photocatalyst in combination with azide ion as a hydrogen atom transfer (HAT) catalyst, provides a direct synthesis of α-tertiary amines, or their corresponding γ-lactams. We anticipate that this methodology will inspire new retrosynthetic disconnections for substituted amine derivatives in organic synthesis, and particularly for challenging α-tertiary primary amines.
Tuning Triplet Energy Transfer of Hydroxamates as the Nitrene Precursor for Intramolecular C(sp3)-H Amidation
Chang, Sukbok,Jung, Hoimin,Keum, Hyeyun,Kweon, Jeonguk
supporting information, p. 5811 - 5818 (2020/04/10)
Reported herein is the design of a photosensitization strategy to generate triplet nitrenes and its applicability for the intramolecular C-H amidation reactions. Substrate optimization by tuning physical organic parameters according to the proposed energy transfer pathway led us to identify hydroxamates as a convenient nitrene precursor. While more classical nitrene sources, representatively organic azides, were ineffective under the current photosensitization conditions, hydroxamates, which are readily available from alcohols or carboxylic acids, are highly efficient in accessing synthetically valuable 2-oxazolidinones and γ-lactams by visible light. Mechanism studies supported our working hypothesis that the energy transfer path is mainly operative.
