Reaction of b-, g-, and d-Chloroalkanamides with Potassium tert-Butoxide in Tetrahydrofuran: Elimination, and Lactamization
摘要:
gamma-and delta-Chloroalkanamides were found to undergo lactamization readily when treated with potassium tert-butoxide in tetrahydrofuran. Raising the reaction temperature may encourage S(N)2 displacement reaction. On the other hand beta-chloroalkanamides only undergo elimination, followed by dimerization and trimerization of the acrylamide initially formed.
Enantioconvergent Alkylations of Amines by Alkyl Electrophiles: Copper-Catalyzed Nucleophilic Substitutions of Racemic α-Halolactams by Indoles
作者:Agnieszka Bartoszewicz、Carson D. Matier、Gregory C. Fu
DOI:10.1021/jacs.9b07875
日期:2019.9.18
classic SN2 reaction of an amine with an alkyl electrophile, both with respect to reactivity and to enantioselectivity. In this study, we describe the development of a user-friendly method (reaction at room temperature, with commercially available catalyst components) for the enantioconvergent nucleophilic substitution of racemic secondary alkyl halides (α-iodolactams) by indoles. Mechanistic studies are
solvent, the reactions could be performed in yields ranging from 40 to 70%. Most of the products were tested for their antimicrobial, antifungal, antioxidant, and cytotoxic (MCF-7) activity. Xanthone, thioxanthone, fluorenone, benzophenone, 2-benzoylpyridine, dibenzofuran, and dibenzothiophene were deprotonated using a base prepared in situ from MCl2·TMEDA (M = Zn or Cd; TMEDA = N,N,N′,N′-tetramethylethylenediamine)
A Samarium(II)-Mediated, Stereoselective Cyclization for the Synthesis of Azaspirocycles
作者:Giuditta Guazzelli、Lorna A. Duffy、David J. Procter
DOI:10.1021/ol8017209
日期:2008.10.2
Unsaturated keto-lactams undergo sequential conjugate reduction-aldol cyclization on treatment with SmI 2 to give syn-spirocyclic pyrrolidinones and piperidinones containing vicinal, fully substituted stereocenters with complete diastereocontrol. The substituent on nitrogen and the lactam ring size have a marked impact on the efficiency of the spirocyclization.
Synthesis of Spirocyclic Pyrazolones by Oxidative C–N Bond Formation
作者:Javier Agejas、Laura Ortega
DOI:10.1021/acs.joc.5b00796
日期:2015.6.19
The two-step synthesis of spirocyclic pyrazolone derivatives from simple and commercially available reagents is described. The unusual reaction of 1,3-dicarbonyls with hydrazines and an iodine-mediated oxidative carbon–nitrogen bond formation, joined in a two-step, one-pot reaction, allows the straightforward synthesis of these spirocycles.
Copper‐Mediated Intramolecular Amidation/C−N‐Coupling Cascade Sequence: Straightforward One‐Pot Synthesis of N‐Aryl γ‐ and δ‐Lactams by Using Amino Acids as Precursors
作者:Sushobhan Chowdhury、Gunjan Chauhan、Ajay Kumar、Bipin Chaturvedi、Chinmaya Behera
DOI:10.1002/ejoc.202200850
日期:2022.11.7
In this work, an operationally simple, one-pot, straightforward synthesis of N-aryl γ- and δ-lactams has been disclosed. Readily available, cheap γ-/δ-amino acids and aryl halides were used as starting materials to synthesize a variety of N-aryl γ- and δ-lactams by using copper-mediated cascade intramolecular amidation/C−N-coupling sequence.