Synthesis of N-amino imides

Grinding and Microwave‐assisted Synthesis of Heterocyclic Molecules in High Yields and Their Biological Evaluation

“…Reported methods for the synthesis of 2‐aminohexahydro‐1 H ‐isoindole‐1,3(2 H )‐dione ( 3a ) and 2‐Amino‐1 H ‐isoindole‐1,3(2 H )‐dione ( 3b ) involve two‐step synthesis and refluxing in a solvent. We have synthesized 2‐aminohexahydro‐1 H ‐isoindole‐1,3(2 H )‐dione ( 3a ; Scheme ), 2‐Amino‐1 H ‐isoindole‐1,3(2 H )‐dione ( 3b ; Scheme ), and 6‐amino‐5 H ‐pyrrolo[3,4‐b]pyrazine‐5,7(6 H )‐dione ( 3c ; Scheme ) by simply grinding a mixture of corresponding dicarboxylic acids ( 1a , 1b , 1c ; Scheme ) and hydrazine hydrate (1:1.2 mol ratio) for 30 min at room temperature.…”

“…Yield: 77%. mp: 202–205°C (lit mp 200–205°C). IR (KBr) ν max : 3377 (NH 2 ), 1669 (C = O), 1476 (Ar) cm −1 .…”

“…Yield 272 mg (82%). mp: 63-65°C (lit [32,33] General procedure for synthesis of azomethine derivatives (6ax-cz).…”

Synthesis of Bicyclic Ethers by a Gold/Palladium/Gold‐Catalyzed Cyclization/Cross Coupling Sequence

“…The starting materials of our study, the β-hydroxyallenes 1a-j, were prepared in two different ways (Scheme 2). The terminally disubstituted allenes 1a-c were obtained by reduction of the corresponding β-allenic esters [10] which were synthesized by either 1,6-cuprate addition to 2-en-4ynoates [11] or by orthoester Claisen rearrangement of propargylic alcohols. [12] In contrast, the β-hydroxyallenes 1d-j were formed by copper-mediated S N 2Ј-substitution of propargylic oxiranes, [8] followed by a protection-deprotection sequence.…”

Elucidation of the Mechanism of the 1,6‐Cuprate Addition to Acceptor‐Substituted Enynes through 13C Kinetic Isotope Effects: Experimental and Theoretical Studies

“…[4] Early NMR spectroscopic investigations have proven the presence of p complexes B, which were characterized by their unique chemical shifts and 13 C, 13 C coupling constants. [5] In contrast, less is known about further intermediates on the way to the allenyl enolates C, whose protonation furnishes b-allenic esters D and derivatives thereof.…”