22217-08-9Relevant articles and documents
Preparation of neuroprotective condensed 1,4-benzoxazepines by regio- And diastereoselective domino knoevenagel-[1,5]-hydride shift cyclization reaction
Tth, Lszl,Fu, Yan,Zhang, Hai Yan,Mndi, Attila,K?vr, Katalin E.,Illys, Tünde-Zita,Kiss-Szikszai, Attila,Balogh, Balzs,Kurtn, Tibor,Antus, Sndor,Mtyus, Pter
, p. 2594 - 2602 (2014)
Condensed O, N- heterocycles containing tetrahydro-1,4-benzoxazepine and tetrahydroquinoline moieties were prepared by a regio- and diastereoselective domino Knoevenagel-[1,5]-hydride shift cyclization reaction of a 4-aryl-2-phenyl-1,4-benzoxazepine deriv
Remodeling and Enhancing Schmidt Reaction Pathways in Hexafluoroisopropanol
Motiwala, Hashim F.,Charaschanya, Manwika,Day, Victor W.,Aubé, Jeffrey
, p. 1593 - 1609 (2016/03/01)
The effect of carrying out two variations of the Schmidt reaction with ketone electrophiles in hexafluoroisopropanol (HFIP) solvent has been studied. When TMSN3 is reacted with ketones in the presence of triflic acid (TfOH) promoter, tetrazoles are obtained as the major products. This observation is in contrast to established methods, which usually lead to amides or lactams arising from formal NH insertion as the major products. The full product profiles of several examples of this reaction are also reported and found to include mechanistically interesting products (e.g., double ring expansion). Application of TfOH promoter in HFIP was also found to promote the reaction of a hydroxyalkyl azide with a ketone, which affords lactams following nucleophilic opening of initially formed iminium ether more efficiently than previously reported methods. (Chemical Equation Presented).
Azido-Schmidt reaction for the formation of amides, imides and lactams from ketones in the presence of FeCl3
Yadav,Reddy, B.V. Subba,Reddy, U.V. Subba,Praneeth
, p. 4742 - 4745 (2008/12/21)
Ketones undergo smooth rearrangement with TMSN3 in the presence of FeCl3 under extremely mild conditions to provide the corresponding amides, imides and lactams in good yields with high selectivity. This method is very useful for the preparation of a wide range of amides, imides and lactams from ketones. The use of FeCl3 makes this method simple, convenient and cost-effective.
Benzodiazepine Analogues. Part 9. Kinetics and Mechanism of the Azidotrimethylsilane-mediated Schmidt Reaction of Flavanones
Kaye, Perry T.,Mphahlele, M. Jack,Brown, Michael E.
, p. 835 - 838 (2007/10/02)
1H NMR spectroscopy has been used to monitor the formation of 1,4-benzoxazepinones and their tetrazolo analogues via azidotrimethylsilane-mediated Schmidt rearrangement of flavanone precursors.Analysis of the kinetic data has permitted the determination of rate coefficients and rationalization of substituent effects.
FLAVONOIDS, XXXVII. RING CONTRACTION AND RING ENLARGEMENT REACTIONS WITH TRIMETHYLSILYL AZIDE IN THE FIELD OF FLAVONOIDS
Litkei, Gy.,Patonay, T.
, p. 47 - 56 (2007/10/02)
The reaction of flavanone with trimethylsilyl azide (TMSA) in trifluoroacetic acid (TFA) afforded by ring expansion, 2,3-dihydro-2-phenyl-1,4-benzoxazepin-5(4H)-one or 2,3-dihydro-2-phenyl-4H-tetrazolo-1,4-benzoxazepine.The same products could be isolated using sodium azide in TFA.An unknown intermediate of the Schmidt reaction was also isolated.Treatment of 2'-hydroxychalcone with TMSA or sodium azide in TFA resulted in isoflavone and trans-3-aminoflavanone.The reaction of 4-substituted 2'-hydroxychalcones with TMSA in dimethylformamide gave, with ring contraction, aurones and flavones.
