169614-59-9Relevant academic research and scientific papers
An Oxidation Study of Phthalimide-Derived Hydroxylactams
Adjei, Bernard L.,Luzzio, Frederick A.
, (2022/01/24)
A systematic study of the oxidation of 3-hydroxy-2-substituted isoindolin-1-ones (hy-droxylactams) and their conversion to the corresponding phthalimides was undertaken using three oxidants. Of special interest was the introduction of nickel peroxide (NiO2 ) as an oxidation system for hydroxylactams and comparison of its performance with the commonly used pyridinium chlorochromate (PCC) and iodoxybenzoic acid (IBX) reagents. Using a range of hydroxylactams, optimal conversions of these substrates to the corresponding imides was achieved with 50 equivalents of freshly prepared NiO2 in refluxing toluene over 5–32 h reaction times. By comparison, oxidations of the same substrates using PCC/silica gel (three equivalents) and IBX (three equivalents) required oxidation times of 1–3 h for full conversion but required lengthier purification. While nominal amounts (~25 mg) of substrate hydroxylactams were used to ascertain conversion, scale-up procedures using all three methods gave good to excellent isolated yields of imides.
Combined Photoredox/Enzymatic C?H Benzylic Hydroxylations
Betori, Rick C.,May, Catherine M.,Scheidt, Karl A.
supporting information, p. 16490 - 16494 (2019/11/03)
Chemical transformations that install heteroatoms into C?H bonds are of significant interest because they streamline the construction of value-added small molecules. Direct C?H oxyfunctionalization, or the one step conversion of a C?H bond to a C?O bond, could be a highly enabling transformation due to the prevalence of the resulting enantioenriched alcohols in pharmaceuticals and natural products,. Here we report a single-flask photoredox/enzymatic process for direct C?H hydroxylation that proceeds with broad reactivity, chemoselectivity and enantioselectivity. This unified strategy advances general photoredox and enzymatic catalysis synergy and enables chemoenzymatic processes for powerful and selective oxidative transformations.
Photoinduced SET phthalimidation of unactivated double bonds and its application to the synthesis of protected phenethylamines
Suau, Rafael,García-Segura, Rafael,Sánchez-Sánchez, Cristobal,Pérez-Inestrosa, Ezequiel,Pedraza, Ana María
, p. 2913 - 2919 (2007/10/03)
Phthalimide, in equilibrium with its conjugate base, adds photochemically to cyclohexene and aryl-substituted alkenes (photophthalimidation). The efficient, predictable regioselective photophthalimidation of styrenes constitutes a synthetically useful process for the preparation of N-phenethyl-phthalimides. A possible mechanism for the photophthalimidation involves the nucleophilic attack of phthalimide anion on the alkene cation-radical generated by single electron transfer to excited phthalimide.
Prostanoids and related compounds. VII. Synthesis and inhibitory activity of 1-isoindolinone derivatives possessing inhibitory activity against thromboxane A2 analog (U-46619)-induced vasoconstriction
Kato, Yoshiaki,Takemoto, Masumi,Achiwa, Kazuo
, p. 529 - 535 (2007/10/03)
We have synthesized a series of novel 1-isoindolinone derivatives, which inhibited the contraction of pig coronary artery induced by U-46619, a thromboxane A2 analog.
Photophthalimidation of unactivated double bonds. Synthesis of protected phenethylamines
Suau, Rafael,Garcia-Segura, Rafael,Sanchez, Cristobal,Pedraza, Ana Maria
, p. 2007 - 2010 (2007/10/03)
At low hydroxide ion concentrations, the photoaddition of phthalimide to cyclohexene, indene or styrene derivatives takes place. The cation radical obtained in the electron transfer from the alkene to excited phthalimide is trapped by phthalimide anion. At high hydroxide ion concentrations concerted [2+2] cycloaddition occurs that yields benzazepinediones, whatever the ionization potential of the alkene. The most suitable reaction conditions can be inferred from the observed fluorescence of phthalimide anion.
Unusually Long Lifetimes of the Singlet Derived from 4-Azido-2,3,5,6-tetrafluorobenzamides
Marcinek, Andrzej,Platz, Matthew S.,Chan, Stephen Y.,Floresca, Rey,Rajagopalan, Krishnan,et al.
, p. 412 - 419 (2007/10/02)
Laser flash photolysis (308 nm, 20 ns, 150 mJ) of 4-azido-2,3,5,6-tetrafluorobenzamides, esters, and thioesters generate singlet nitrenes which can be intercepted with pyridine to produce strongly absorbing ylides.It was possible to resolve the rate of formation of the ylides as a function of pyridine concentration.This has lad to direct measurements of the absolute rate constants of (a) the reaction of the nitrene with pyridine, (b) ring expansion of the nitrene to a ketenimine, and (c) singlet to triplet nitrene intersystem crossing.
Photodecarboxylation of N-Phthaloyl-α-amino Acids
Sato, Yasuhiko,Nakai, Hideo,Mizoguchi, Tomishige,Kawanishi, Masazumi,Hatanaka, Yasumaru,Kanaoka, Yuichi
, p. 1263 - 1270 (2007/10/02)
N-Phthaloylglycine (1a) was irradiated with a high pressure mercury lamp to give N-methylphthalimide (2a) in an excellent yield.N-Phthaloyl derivatives 1b-k of other α-amino acids also afforded the decarboxylated products 2b-k.In the cases of N-phthaloylserine (11) and di-phthloylcystine (1m), N-vinylphthalimide (3) was isolated as a major product.On the other hand, N-phthaloylmethionine (11a) and methyl N-phthaloylmethionate (11b) were treated in the same manner to give the aza-thiacyclo-heptanol derivatives 12a-b having a new ring system.Solvent effects and possible pathways of these reactions were examined.Keywords- N-phthaloyl-α-amino acid; photolysis; decarboxylation; cyclization; efficiency; solvent effect; υ-hydrogen abstraction
