Summary A second method for the synthesis of 8-bromo-3-methoxyfluoranthene from 2-bromo-7-methoxyfluorene is described. The autoxidation of fluorene derivatives including the 9-carboxylic acids and of related compounds, particularly 4-α-cyanobenzyl-7−oxo-7H-benz[de]anthracene, is discussed. Unsuccessful attempts to prepare 3-bromofluorene-9-acetic acid in good yield are reported.
The synthesis is reported of a series of apolar nematic liquid crystals incorporating an alkoxyalkoxy chain attached in a terminal position to the molecular core. The dependence of the mesomorphism and phase transition temperatures on the nature of the terminal chain with one, two or three oxygen atoms was studied. Some compounds with a completely alicyclic molecular core and a terminal 2‐methoxyethoxy chain exhibit a nematic phase with a low melting point, birefringence and viscosity and a relatively high clearing point in the absence of smectic phases. They do not to absorb light in the near UV and may be useful as components of UV‐stable nematic mixtures for use in photoluminescent liquid crystal displays. The presence of the methoxyethoxy chain leads to a relatively large dipole moment perpendicular to the molecular long axis.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Optical Activity of ElectrolytesNeil CampbellNeil CampbellMore by Neil CampbellCite this: J. Phys. Chem. 1931, 35, 4, 1143–1155Publication Date (Print):April 1, 1931Publication History Published online1 May 2002Published inissue 1 April 1931https://doi.org/10.1021/j150322a019RIGHTS & PERMISSIONSArticle Views28Altmetric-Citations1LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (596 KB) Get e-Alerts
Abstract Abstract We describe an improved synthesis for a [4 + 6] imine-linked cage, which was shown recently to exhibit microporosity in the crystalline state and which can be converted by recrystallization to produce either porous or nonporous polymorphs. The original methodology for the synthesis of this molecule resulted in poor yields (approximately 35%). Here, we demonstrate that the cage can be prepared in almost 100% yields and can be isolated with high chemical purity. Keywords: Cageiminemicroporous ACKNOWLEDGMENTS We thank the Centre for Materials Discovery for use of the facilities. We thank the North West Development Agency (UK) and Knowledge Centre for Materials Chemistry for funding (D. P. L.). A. I. C. holds a Royal Society Wolfson Research Merit Award.