Indane aldehyde

Materials. The commercially available aldehydes were distilled prior to use and stored at 0°C under argon. The cyclohexene- and cyclopentene- aldehydes, and the indane aldehyde (see Table) were gifts from Professor E. Piers of this department. The Ru(TPP)(PPh3)2 complex (1) was prepared from Ru(TPP)(CO)(EtOH) and PPh3 (1,7), while Ru(TPP)(CO)(tBu2POH), was prepared from the carbonyl (ethanol) adduct by treatment with tBu2PCl (1). The phosphines were from Strem Chemicals, and the ruthenium was obtained as RuCl Ol O from Johnson, Matthey Limited. 

In the presence of the indane aldehyde, additional somewhat irreversible waves are seen at ( wO.l V), which probably refer to some Ru(III) intermediates (10) involved in the catalysis. In the corresponding phenylacetaldehyde system, additional waves are seen at about -0.08 and +0.08 V. On adding nBuoP to the indane aldehyde system, waves are seen at 0.30 V [RuIII(TPP)(nBu3P)2 + e RuII(TPP)(nBu3P)2]> and M).90 V [due to the couple shown... 

The biradicals generated via thermolysis of 1 are intercepted with dienes, furans, " and hydrazones of unsaturated aldehydes to yield indanes. Thermolysis of 1 in the presence of anthracene (346) provides convenient access to homotrypticene 347. ... 

Sodium 5,8,11,14-eicosatetraenoate, 3803 Sodium ethoxyacetylide, 1474 1,1,2,3-Tetrachloro-1,3-butadiene, 1385 f Tetrahydrofuran, 1607 Tetrahydronaphthalene, 3294 f Tetrahydropyran, 1959 Tridecanal, 3613 f Vinyl acetate, 1527 f 4-Vinylcyclohexene, 2999 See Indane-2-aldehyde ACETYLENIC COMPOUNDS ALKALI METALS ALKENES ALKYNES... 

Diels-Alder reaction of 2-bromoacrolein and cyclopentadiene using 10 mol% of titanium catalyst 74 gave the synthetically versatile (R)-bromoaldehyde adduct 75 in 94% yield, 67 1 exo. endo diastereoselectivity, and 93% ee. The absolute stereochemical outcome of the reaction is consistent with the proposed transition state assembly 76 in which the dienophile coordinates at the axial site of the metal, proximal to the indane moiety through Ji-attractive interactions. In this complex, the 7t-basic indole and the Ji-acidic dienophile can assume a parallel orientation facilitated by the octahedral geometry of the transition metal. The aldehyde would then react through a preferential s-cis conformation (Scheme 17.27).54... 

Shu-Jiang and co-workers [76] have developed a green approach for the synthesis of biologically important indeno[2,l-c]pyrazolo[5,4-/7]pyridines 36 via a MCR of a suitable aldehyde, 3-methyl-l-phenyl-l//-pyrazol-5-amine and 1,3-indane-dione in water under microwave irradiation without the aid of any catalyst. This protocol has the prominent advantages of being environmentally benign and having... 

It was noted in Section 3 that unsaturated acyl halides often formed anomalous products. This tendency is even more pronounced in the case of aldehydes. The decarbonylation of 2-allylbenzaldehyde gives a high yield of indan, and very... 

This e c o-peroxide rearranged readily to form the /ra s-benzene trioxide 144 and gave trans-benzene dioxide 142 upon reaction with triphenylphosphite. A similar addition reaction occurred between singlet oxygen and indan 8,9-oxide 7 to yield a further endo-peroxide. An endo-peroxide adduct of an oxepin was also formed when singlet oxygen reacted with 1-benzoxepin 100. Upon deoxygenation with trimethylphosphite, the latter peroxide yielded an aldehyde. ... 

Schreiber and co-workers demonstrated that an indan (PyBox)-Cu(II) complex (140) was able to catalyze the P-3CR (Scheme 5.43) [86]. Nevertheless, the enantio-enriched Passerini adduct was obtained only when the chelating aldehyde was used as a reaction partner. 

Hydrogenation of Knoevenagel products of 2,4-alkanediones over Raney nickel provides a simple route to 3-substituted 2.4-diones. Alternatively, reductive deacetylation can be accomplished using tetracarbonylhydridoferrate(0) in ethanol to prepare alkyl ketones. If the reaction is carried out in THF or acetone, exclusive reduction of the a,p-unsaturated double bond is observed. - Reactions of aldehydes with cyclic 1,3-diketones generally lead to the formation of Michael adducts under standard conditions. Indane-l,3-dione (103) yields Knoevenagel products with different aldehydes, ketones and ketimines, whereas perinaphthindane-l,3-dione (KM) gives the Michael adducts. ... 

The reactivity of pyridazine-3- and 4-carbaldehydes towards active methylene reagents under the conditions of Knoevenagel, Wittig, and Hantzsch-type reactions has been examined. The 4-aldehyde reacts readily with malononitrile and methyl cyanoacetate, and less readily with triethyl phos-phonoacetate, indane-l,3-dione and alkyl acetoacetates/ammonia (e.g.. Scheme 52). Condensation with nitroethane is successful, but nitromethane gives an unstable intermediate which decomposes. The 3-aldehyde has similar reactivity to the 4-aldehyde, but some reactions are unsuccessful due to reduced reactivity, or instability of the products <90JHC1313>. 

The ready availability of the 3-aldehyde (156) has resulted in its chemistry being widely studied.Under azlactone-forming conditions, it was converted into the oxazolones (158), which on acid hydrolysis gave the conjugated acid (159) - a convenient intermediate. Condensation with indane-l,3-dione, thiohydantoin, hydroxylamine, and various hydrazines gave the expected... 

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