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Sterically Hindered Di- and Triarylmethane Dyes Useful for Molecular Matrix Printing

IP.com Disclosure Number: IPCOM000047433D
Original Publication Date: 1983-Nov-01
Included in the Prior Art Database: 2005-Feb-07
Document File: 2 page(s) / 28K

Publishing Venue

IBM

Related People

Ferrante, M: AUTHOR [+2]

Abstract

A promising class of compounds has been identified which combines the desirable property of reaction with bromine to produce a colored product with inertness towards photochemical oxidation, thus precluding background formation. The feature that makes these compounds special is steric hindrance around the central carbon atom, which imparts the unusual property of resistance to photochemical oxidation; the majority of di- and triarylmethanes in the literature are not resistant. Two representative examples are 14-Benzyldibenzo-(a,j)-xanthene 1 (Y=O, X=R1=H,R2=Benzyl) and 14-Methylenedibenzo-(a,j)-xanthene 1 (Y=O,X=H, R1=R2=CH2. Both of these show no background and yield a red product on reaction with bromine.

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Sterically Hindered Di- and Triarylmethane Dyes Useful for Molecular Matrix Printing

A promising class of compounds has been identified which combines the desirable property of reaction with bromine to produce a colored product with inertness towards photochemical oxidation, thus precluding background formation. The feature that makes these compounds special is steric hindrance around the central carbon atom, which imparts the unusual property of resistance to photochemical oxidation; the majority of di- and triarylmethanes in the literature are not resistant. Two representative examples are 14-Benzyldibenzo- (a,j)-xanthene 1 (Y=O, X=R1=H,R2=Benzyl) and 14-Methylenedibenzo-(a,j)- xanthene 1 (Y=O,X=H, R1=R2=CH2. Both of these show no background and yield a red product on reaction with bromine. Other such compounds are depicted by structures 2 and 3 where Y can be oxygen, nitrogen or sulfur, R1 through R4 can be any alkyl, aryl or other groups that together impart photochemical stability while allowing reaction with bromine (such as hydroxyl), and X can be any combination of the usual chemical substituents that are employed to control properties by electronic or steric means. Examples of this additional derivatization are 2,12-dihydroxy-14-(3-nitrophenyl)dibenzo-(a,j)- xanthene 1 (Y=0,X=2,12- dihydroxy,R1=H1R2 =3- nitrophenyl) and Bis(6-bromo- 2-hydroxynaphthyl)- 2'-chlorophenylmethane 3 (Y=0,X=6-bromo, R1=H,R2=2- chlorophenyl).

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