Indane dimerization products obtained by treatment of N-acylindan-1-amines with ethyl polyphosphate (EPP)

The Dimerisation of 5,6-Dimethoxy-Indene

“…This compound had been prepared by dehydration of 3 with thionyl chloride or oxalyl chloride and an erroneous structure had been assigned. 2,3 Later, 4 this dimer was obtained by treatment of the indanone 2 with aluminum trichloride and subsequent Clemmensen reduction, and its structure was corrected to 5, which has now been confirmed herein by assignment of the 1 H and 13 C NMR spectra, using 2D NMR data (COSY, HSQC and HMBC).…”

Dehydration of Alcohols Catalysed by Heteropolyacids Supported on Silica

“…The 1,2,3,4-tetrahydronaphth-1-ol 7 and indanol 8, both commercial compounds, afforded the corresponding alkenes 1,2-dihydronaphthalene 7a and indene 8a, also commercial compounds. Furthermore, in both case, the formation of the dimeric compounds 7b and 8b 13 was observed. Starting alcohols 7 and 8 were completely transformed into dimers 7b and 8b when heated under reflux during 3 hours and 1.5 hours respectively.…”

NMR analysis of 6‐(2′,3′‐dihydro‐1′H‐inden‐1′‐yl)‐1H‐indene

“…3(a) originates from an impurity]. Table 2 shows that the absolute magnitude of the geminal coupling constant 2 The described characteristic patterns could be used as a reliable sign of the presence of the structural element 3 in compounds of hydrocarbon mixtures.…”

“…Their yield and relative quantity depended highly on the reaction temperature and the acid used. The main component of the dimer fraction was 2-(2 0 ,3 0 -dihydro-1 0 H-inden-1 0 -yl)-1H-indene 2,3 and the content of other dimers amounted to 1-2% (minor dimers). Among the minor dimers, a product of the alkylation of 1H-indene with 2,3-dihydro-1H-inden-1-yl carbonium ion was identified as 6-(2 0 ,3 0 -dihydro-1 0 H-inden-1 0 -yl)-1H-indene.…”