686347-86-4

Upstream product

• 79562-21-3 9-hydroxy-9-ethynyl-9H-thioxanthene 
• 78250-17-6 5-methoxy-benzofluoren-7(H)-one 
• 78250-21-2 5-hydroxy-7-oxo-7H-benzo(c)-fluorene 
• 492-22-8 thio-xanthene-9-one 
• 686347-83-1 spiro[13-oxoindeno[2,1-f]naphtho[1,2-b]pyran-3,9'-thioxanthene] 
• 78265-13-1 1,4-dimethoxynaphthalene-2-carboxylic acid 
• 78265-14-2 1,4-dimethoxy-2-naphthoyl chloride 
• 127536-35-0 1,4-dimethoxynaphthalene-2-carboxylic acid methyl ester 

Relevant academic research and scientific papers

The effect of a sulphur bridge on the photochromic properties of indeno-fused naphthopyrans

The synthesis of four new 2,2-diphenyl-2H-naphtho[1,2-b]pyrans with a fused indeno group at the f face and a sulphur junction between the 2,2-phenyl groups is described. The photochromic properties in solution of these novel compounds were investigated under continuous irradiation. Compared to known indeno-fused naphthopyrans, these new compounds showed a significant bathochromic shift in the spectra of the open forms, faster ring closure kinetics and an expected decrease in the colourabilities.