Issue 4, 1970

Cyclopenta[d]pyridazines and cyclopenta[d][1,2]oxazines

Abstract

Usually cyclopenta[d]pyridazines and cyclopenta[d][1,2]oxazines are protonated and react with other electrophiles in the five-membered ring at the 5- or the 7-position, although 2-phenyl-1,4-di-t-butylcyclopenta[d]pyridazxine can be brominated at the 6-position. The pyridazines are more reactive than the oxazines. Both pyridazines and oxazines can be brominated; the pyridazines, but not the oxazines, react with triethyl orthoformate to give aldehydes. The salts of both pyridazines and oxazines condense with diphenylcyclopropenone to form salts in which the positive charge is shared between the three-membered ring and the hetero-atoms; the pyridazinium salts also condense with p-dimethylaminobenzaldehyde to give intensely coloured products. N.m.r. spectra indicate more delocalisation of the double bonds in the pyridazines than in the oxazines.

Article information

Article type
Paper

J. Chem. Soc. C, 1970, 610-616

Cyclopenta[d]pyridazines and cyclopenta[d][1,2]oxazines

D. Lloyd and N. W. Preston, J. Chem. Soc. C, 1970, 610 DOI: 10.1039/J39700000610

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements