Indan-2-ones, formation

Tetralin shows evidence in n.m.r. spectroscopy, similar to that mentioned above, for the formation of one or more addition complexes. Tetralin (like indan) is known to undergo acetoxylation. ... 

Most recently, Lappert and co-workers have found that the carbonylation of bis(i7-cyclopentadienyl)titanabenzocyclopentene resulted in the formation of Cp2Ti(CO)2 (1) and indan-2-one 47a). 

Catalysis of the enolization of indan-2-one (96 pKa = 12.2) by a-, j8-, y-, and modified cyclodextrins (of similar pKa) indicate that the latter act as general bases.139 There is also an inclusion component to the catalysis saturation kinetics consistent with 1 1 binding are observed for enolate formation. 

Consider now the enthalpies of formation of our diverse indane heterocycles and corresponding one-ring species formed by de-benzoannelation (Table 1). De-benzoannelation resulting in aromatic one-ring species is generally more favorable than processes involving non- or antiaromatic species. The enthalpy of formation difference for aromatic species is typically 50-60 kJ mol-1, for nonaromatic species typically ca. 30 kJ mol-1, and for antiaromatic species ca. 24 kJ mol-1. The difference of the enthalpies of formation between the benzoannelated and one-ring dithiol-2-thiones is —11 kJ mol-1. No explanation for this discrepancy is apparent. 

Einaga, H., Nojima, M. and Abe, M. (1999) Photooxygenation ( 02) of silyl enol ethers derived from indan-l-ones competitive formation of tricyclic 3-siloxy-... 

Reduction of dispiro[bis(cyclopropane)indan]yl methyl oxalate 50 led to the formation of all three possible products derived from the cleavage of one cyclopropane ring. ... 

Qualitative indications concerning the ease of formation of various ring sizes have been indicated in the Introduction. Early studies using substrates that could give mixtures of products with various ring sizes showed that six-membered ring formation is always preferred over the formation of five- and seven-membered rings (equations 7-9). The examples shown in equations (10) and (11) indicate that indan-l-ones are formed more easily than benzosuberones. 

The reactions of the ferrio-silanediol Cp(OC)2Fe-Si(Me)(OH)2 with trimethylgallane and -indane, respectively, result in the formation of the heterosiloxanols 4e,f. Only one OH function of the ferrio-silanediol is transformed, irrespective of the amount of trimethylgallane or -indane used. The... 

Tricarbonyl-butadieneiron reacts with AICI3 to produce a ca. 5 % yield of a mixture of cyclopent-2-enone and cyclopent-3-enone. ° Notwithstanding this low yield the method is useful, for example, in the formation of indan-2-one. 

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