1H-1,3-Diazepines and Ketenimines from Cyanotetrazolopyridines

Cyano-substituted tetrazolo[1,5-a]pyridines/2-azidopyridines 8T and 15T undergo thermal ring opening to the azides 8A and 15A. Solution photolysis causes nitrogen elimination and ring expansion to 1,3-diazacyclohepta-1,2,4,6-tetraenes 10 and 17, which react with alcohols to afford 2-alkoxy-1H-1,3-diazepines, with secondary amines to 2-dialkylamino-5H-1,3-diazepines, and with water to 1,3-diazepin-2-ones (12–14, 19, 21). Argon matrix photolysis of the azides affords the diazacycloheptatetraenes 10 and 17 as principal products together with ring-opened dicyanovinylketenimines 11 and 18. The matrix-isolated species were identified on the basis of comparison of the infrared spectra with those calculated at the B3LYP/6–31+G* level.

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Examinations of the Matrix Isolation Fourier Transform Infrared Spectra of Organic Compounds: Part XV

Applied Spectroscopy ◽

10.1366/0003702894204047 ◽

1989 ◽

Vol 43 (6) ◽

pp. 1004-1008 ◽

Cited By ~ 3

Author(s):

W. M. Coleman ◽

Bert M. Gordon

Keyword(s):

Fourier Transform ◽

Infrared Spectra ◽

Matrix Isolation ◽

Fourier Transform Infrared ◽

Argon Matrix ◽

Fourier Transform Infrared Spectra ◽

The Matrix ◽

Ft Ir ◽

Oil Components ◽

Search Routine

Matrix isolation Fourier transform infrared spectra (MI/FT-IR) of a series of essential oil components have been described. Clear, well-defined differences were detected in the MI/FT-IR spectra of compounds having minor differences in their structure. A library search routine was found to correctly identify components of interest when visual differences were not clearly evident. The presence of discrete conformers in the argon matrix resulted in the presence of split absorptions in the carbonyl band for selected compounds.

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Ring opening and ring expansion of 8-cyano-tetrazolo[1,5-a]pyridine with secondary amines. Reactions of azides, tetrazoles and nitrenes with nucleophiles, Part 2

ARKIVOC ◽

10.3998/ark.5550190.0010.604 ◽

2009 ◽

Vol 2009 (6) ◽

pp. 30-37 ◽

Cited By ~ 3

Author(s):

Chris Addicott ◽

Paul V. Bernhardt ◽

Curt Wentrup

Keyword(s):

Ring Opening ◽

Ring Expansion ◽

Secondary Amines

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Examinations of the Matrix Isolation Fourier Transform Infrared Spectra of Organic Compounds: Part XVI

Applied Spectroscopy ◽

10.1366/0003702894203895 ◽

1989 ◽

Vol 43 (6) ◽

pp. 1008-1016 ◽

Cited By ~ 8

Author(s):

W. M. Coleman ◽

Bert M. Gordon

Keyword(s):

Fourier Transform ◽

Ir Spectra ◽

Vapor Phase ◽

Infrared Spectra ◽

Condensed Phase ◽

Matrix Isolation ◽

Absorption Bands ◽

Argon Matrix ◽

The Matrix ◽

The Impact

Information concerning the matrix isolation Fourier transform infrared spectra of a series of alkanes, esters, lactones, lactams, phenols, alcohols, amides, alkenes, and ketones is presented. A comparison between the characteristics of the spectra in two matrices (argon and xenon) as well as in the absence of any matrix (bare gold disk) is drawn. The impact of these matrices on the characteristics of the IR spectra is compared with the impact observed when spectra are gathered in the vapor phase as well as the condensed phase/solid state. For the majority of compounds studied, the major absorption bands of each class of compound fall between higher values for the vapor phase and lower values for the condensed phase when either argon or xenon is used as the matrix gas. The few exceptions are discussed. The absorption bands found in the xenon matrix are usually at a lower energy than are comparable bands in the argon matrix. In most all cases, the values of absorptions for compounds on the bare disk were lower than the comparable values found in the argon matrix. These results represent the first extensive study at 10 K of the effect of different matrix gas hosts and document the proposal that preconceptions of noble gases as inert hosts for the examination of FT-IR spectra at low temperature are not valid.

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Formation and structure of molecular O:P-F. Mass spectrometry, infrared spectra of the matrix isolated species and ab initio calculations

Journal of the American Chemical Society ◽

10.1021/ja00285a004 ◽

1986 ◽

Vol 108 (25) ◽

pp. 7905-7911 ◽

Cited By ~ 44

Author(s):

Reinhart. Ahlrichs ◽

Ralf. Becherer ◽

Michael. Binnewies ◽

Horst. Borrmann ◽

Michael. Lakenbrink ◽

...

Keyword(s):

Mass Spectrometry ◽

Ab Initio Calculations ◽

Ab Initio ◽

Infrared Spectra ◽

The Matrix ◽

Isolated Species

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Examinations of the Matrix Isolation Fourier Transform Infrared Spectra of Organic Compounds: Part VIII

Applied Spectroscopy ◽

10.1366/0003702884428130 ◽

1988 ◽

Vol 42 (2) ◽

pp. 304-309 ◽

Cited By ~ 8

Author(s):

W. M. Coleman ◽

Bert M. Gordon

Keyword(s):

Fourier Transform ◽

Organic Compounds ◽

Vapor Phase ◽

Infrared Spectra ◽

Matrix Isolation ◽

Fourier Transform Infrared ◽

Argon Matrix ◽

Fourier Transform Infrared Spectra ◽

The Matrix ◽

Ft Ir

Matrix isolation Fourier transform infrared (MI/FT-IR) data has been presented that documents the presence of discrete conformers in an argon matrix for a series of ketones. The distribution of conformers in the matrix was related to the structure of the molecule, in that rigid structures (i.e., small rings, bicyclic systems, and unsaturated systems) displayed simple carbonyl absorption patterns relative to those of their less rigid counterparts. Also, conformer isolation was seen for halosubstituted ketones. These results are in agreement with previous findings concerning the vapor-phase (VP) spectra of these molecules.

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Synthesis and Antiproliferative Activity of Phosphorus Substituted 4-Cyanooxazolines, 2-Aminocyanooxazolines, 2-Iminocyanooxazolidines and 2-Aminocyanothiazolines by Rearrangement of Cyanoaziridines

Molecules ◽

10.3390/molecules26144265 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4265

Author(s):

Victor Carramiñana ◽

Ana M. Ochoa de Ochoa de Retana ◽

Francisco Palacios ◽

Jesús M. de los de los Santos

Keyword(s):

Ring Opening ◽

Human Lung ◽

Ring Expansion ◽

Moderate Activity ◽

A549 Cell Line ◽

One Pot ◽

Acidic Conditions ◽

Lung Adenocarcinoma A549 ◽

High Yields

Several phosphorus-substituted N-acylated cyanoaziridines 2 and N-carbamoylated cyanoziridines 5 were prepared in good to high yields. N-Acylated cyanoaziridines 2 were used, after ring expansion, in an efficient synthesis of oxazoline derivative 3a and in a completely regio-controlled reaction in the presence of NaI. Conversely, N-carbamoyl cyanoaziridines 5 reacted with NaI to obtain a regioisomeric mixture of 2-aminocyanooxazolines 7. Mild acidic conditions can be used for the isomerization of N-thiocarbamoyl cyanoaziridine 6a into a 2-aminocyanothiazoline derivative 8a by using BF3·OEt2 as a Lewis acid. Likewise, a one pot reaction of NH-cyanoaziridines 1 with isocyanates obtained 2-iminocyanooxazolidines 9 regioselectively. This synthetic methodology involves the addition of isocyanates to starting cyanoaziridines to obtain N-carbamoyl cyanoaziridines 5, which after the ring opening, reacts with a second equivalent of isocyanate to give the final 2-imino cyanooxazolidines 9. In addition, the cytotoxic effect on the cell lines derived from human lung adenocarcinoma (A549) was also screened. 2-Iminooxazolidines 9 exhibited moderate activity against the A549 cell line in vitro. Furthermore, a selectivity towards cancer cells (A549) over non-malignant cells (MCR-5) was detected.

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Ring expansion and ring opening of 3-halooxindoles with N-alkoxycarbonyl-O-tosylhydroxylamines for divergent access to 4-aminoquinolin-2-ones and N-Cbz-N’-arylureas

Organic Chemistry Frontiers ◽

10.1039/d0qo01335h ◽

2021 ◽

Author(s):

Wei-Cheng Yuan ◽

Jian Zuo ◽

Shu-Pei Yuan ◽

Jian-Qiang Zhao ◽

Zhen-Hua Wang ◽

...

Keyword(s):

Ring Opening ◽

Ring Expansion

The reaction of N-alkoxycarbonyl-O-tosylhydroxylamines with indol-2-ones in situ generated from 3-halooxindoles has been developed for divergently accessing 4-aminoquinolin-2-ones and N-Cbz-N’-arylureas in good to excellent yields.

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Direct ring-opening of lactide with amines: application to the organo-catalyzed preparation of amide end-capped PLA and to the removal of residual lactide from PLA samples

Polymer Chemistry ◽

10.1039/c4py00973h ◽

2015 ◽

Vol 6 (6) ◽

pp. 989-997 ◽

Cited By ~ 15

Author(s):

Aurélie Alba ◽

Olivier Thillaye du Boullay ◽

Blanca Martin-Vaca ◽

Didier Bourissou

Keyword(s):

Ring Opening ◽

Secondary Amines ◽

Primary And Secondary Amines

Spontaneous ring-opening of lactide by primary and secondary amines has been applied to the preparation of well-defined amide end-capped PLA and to the removal of unreacted lactide from PLA samples.

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