5- naphthalimide

Other Heterocyclic Systems. Naphthalimides (15), where R = —NHCOR, are derivatives of 4-anTinonaphthalimide (69) and are used in plastics. The alkoxynaphthalimides (15, R = OCH ) (70,71) are of particular interest as fluorescent whitening agents. 

Naphthalimides are prepared from naphthaUc anhydride obtained from naphthalene-1,8-dicarboxyhc acid, ie, the oxidation product of acenaphthene or its derivatives, by reaction with amines. They are utilized for synthetic fibers such as polyesters. 

The main chain of these polymers contains, as the principal component, five- or six-membered heteroaromatic rings, ie, imides, which are usually present as condensed aromatic systems, such as with benzene (phthalimides, 3) and naphthalene (naphthalimides, 4) rings. 

Recently, the pyrazole group containing bisphenols have been synthesized from activated aromatic dihalides and 3,5-bis (4-hydroxy phenyl)-4-phenyl pyrazole or 3,5-bis(4-hydroxy phenyl)-1,4-diphenyl pyrazole. A novel synthesis of imido aryl containing bisphenols has been reported [32]. N-substituted l,4-bis(4-hydroxy phenyl)-2,3-naphthalimides were prepared from phenolphthalein and copolymerized with aromatic sulfone or ketone difluorides to obtain the poly(imidoaryl ether) sulfones/ ketones. 

Herbert and Hay reported a bisphenolic monomer, 3,8-bis(4-hydroxyphenyl)-A-phenyl-1,2-naphthalimide (Table 6.1), as well as its corresponding polyf V-phenyl imido aryl ether sulfone) via transimidization reactions with hydrazine monohydrate, aliphatic amines, and an amino acid.193 These polysulfones with... 

Bis(4-hydroxyphenyl)-lV-phenyl-l,2-naphthalimide, 354, 355 4,4 -Bis(4-hydroxyphenyl)pentanoic acid (BHPA), 355, 356 Bisnitroimides, 346 Bisphenol-A, 112 Bisphenol-A-based benzoxazines... 

In general and as expected, brighteners of relatively small molecular size are most suitable for application by exhaustion. Less volatile compounds of larger molecular size tend to be preferred for pad-thermosol application or for incorporation in the polymer mass. Commercially important for exhaust application are the previously mentioned pyrene derivative 11.22, the naphthalimide 11.23, the bis(benzoxazolyl)ethene 11.35, the bis (benzoxazolyl) thiophene 11.36, the distyrylbenzene 11.37 and the stilbene bis (acrylic ester) derivative 11.38. Products of the 11.35 type show excellent light fastness but only moderate fastness to sublimation. In view of this volatility they can be used in the transfer printing of polyester. 

The naphthalimide 11.23 is manufactured from acenaphthene by sulphonation, oxidation to the naphthalic anhydride derivative and conversion to 4-methoxy-N-methylnaphthal-imide as outlined in Scheme 11.14. 

At one time disperse-type FBAs, such as pyrazoline, coumarin or naphthalimide derivatives, were commonly used to brighten acrylic fibres. Today all the important brighteners for these fibres are cationic in character and can be divided into two main categories ... 

Synthesis of the coumarin derivative 11.58 containing two isomeric triazolyl rings is indicated in Scheme 11.24- The substituted pyrazolyl derivative of naphthalimide 11.59 is prepared by a reaction sequence somewhat similar in principle to that already shown in Scheme 11.14, using 4-amino-1,3,5-trimethylpyrazole in the penultimate step followed by quaternisation. 

Vazquez ME, Blanco JB, Imperiali B (2005) Photophysics and biological applications of the environment-sensitive fluorophore 6-N, N-Dimethylamino-2, 3-naphthalimide. J Am Chem Soc 127 1300-1306... 

The thiadiazole naphthalimide 84 was synthesized from the 2-thiobenzyl aniline 83 under similar conditions (Equation 25) <2003BML3513>. 

Scheme 8 Naphthalene diimide (18), pyrazinonaphthalimide (19), and bis pyrazino-naphthalimide derivatives (20, 21).

Since their commercial introduction during the 1940s as components of proprietary detergents and laundry preparations, these products have found extensive usage in the whitening of paper and textile materials. Disperse FBAs are available for whitening hydrophobic fibres and solvent-soluble FBAs impart fluorescence to oils, paints, varnishes and waxes. Approximately 75% of commercially established FBAs are stilbene derivatives with inherent substantivity for paper and cellulosic textiles, but the remainder come from about twenty different chemical classes. These include aminocoumarins (6%), naphthalimides (3%), pyrazoles and pyrazolines (each about 2%), acenaphthenes, benzidine sulphones, stilbene-naphthotriazoles, thiazoles and xanthenes (each about 1%). FBAs of these and other chemical types are discussed in detail in Chapter 11 of Volume 2. 

Parkesh R, Lee TC, Gunnlaugsson T (2007) Highly selective 4-amino-1,8-naphthalimide based fluorescent photoinduced electron transfer (PET) chemosensors for Zn(II) under physiological pH conditions. Org Biomol Chem 5 310-317... 

Cross J-P, Lauz M, Badger PD et al (2004) Polymetallic lanthanide complexes with PAMAM-naphthalimide dendritic ligands luminescent lanthanide complexes formed in solution. J Am Chem Soc 126 16278-16279... 

Qu Y, Hua J, Yiang Y, Tian H (2009) Novel side-chain naphthalimide polyphenylacetylene as a ratiometric fluorescent chemosensor for fluoride ion. J Polym Sci A Polym Chem 47 1544-1552... 

In the second series, the fluorophore NBD was linked to the carboxy terminus via a piperazine spacer as in 188 or via 6-(ethylamino)-iV-butyl-l,8-naphthalimides and yielded the fluorescently labeled compound 189 . ... 

Coumarins are one of several classes of fluorescent structures containing the carbonyl group as an essential molecular substructure and showing the features typical of donor-acceptor molecules. Others include naphthalimides, perylene esters, perylenediimides, benzanthrones, anthraquinones, benzoxanthones and benzothioxanthones (see below). 

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