Novel benzofuran dyes
AssigneeEastman Kodak Company
InventorsChin H. Chen, John L. Fox
Life of this patent
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Abstract
A 6-tertiary amino-2-(Z.dbd.CH--)benzofuran dye is disclosed, where Z represents the atoms providing an electron withdrawing group and a conjugated methine linkage completing a resonant dye chromophore including the 6-tertiary amino group as an electron donor and the electron withdrawing group as an electron acceptor. The dyes are formed by condensing a 6-tertiary amino-2-formylbenzofuran with an electron withdrawing dye nucleus precursor containing an active methyl or methylene site. The dyes exhibit bathochromically shifted absorption peaks.
Claims6
A dye which satisfies the formula:
- ##STR33## where E.sup.1 and E.sup.2 are independently selected to satisfy the formula:
- ##STR34## R.sup.1, R.sup.2, and R.sup.5 each independently represent hydrogen, alkyl, or aryl;
- R.sup.3 and R.sup.4 each independently represent alkyl;
- or
- at least one of the substituent pairs represented by R.sup.1 and R.sup.4, R.sup.2 and R.sup.3, and R.sup.3 and R.sup.4 complete a 5- or 6-membered ring containing the formula nitrogen atom as the sole heteroatom;
- with the proviso that at least one of E.sub.1 or E.sub.2 are such that R.sub.1 -R.sub.4 complete a julolidine ring structure;
- X.sup.1 and X.sup.2 are independently hydrogen, alkyl, or aryl or together complete a 5 to 7 membered ring and satisfy the formula:
- ##STR35## where n is 2 to 4;
- Y is --NR.sup.10 -- or --O--;
- and
- R.sup.10 is lower alkyl of from 1 to 3 carbon atoms or phenyl;
- alkyl, with the exception of said lower alkyl, in each occurrence containing from 1 to 8 carbon atoms and aryl in each occurrence being phenyl or naphthyl.
2,5-Bis(2,3,6,7-tetrahydro-1H,5H-benzo-[i,j ]furano[3,2-g]quinolizin-9-yl-methylene)cyclopentanone.
Dependencies are inferred from the claim text.