Indene moiety

In order to avoid as far as possible double bond positional isomers, a problem quite common in drugs with indene moieties, N-trityl-2-hydroxymethylmorpholine (23) was reacted with the potassium. salt of 4-hydroxy-1-indanone (24) in DMSO solvent to give condensation product 25 in good yield. Reduction of 25 with LLAIH produced the hydroxyindane which was dehydrated and deprotected with HCl to give indeloxazine (26) [8]. 

Raeppel, E, Weibel, J.-M., and Heissler, D., Synthesis of the trans-syn-trans perhydrobenz[e]indene moiety of the stellettins and of the stelliferins. Tetrahedron Lett., 40, 6377, 1999. 

Figure 4.4 Fluorinated polyamides containing indene moiety [8],...

Ding and Bikson described prepared the dens membranes from aromatic PAs containing 2,3-dihydro-l,l,3-trimethyl-lH-indene moieties in the main chain and investigated their gas transport properties [81]. The membranes showed high gas permeability coefficients and gas separation factors. The nonsymmetric and non-planar diacid residue results in desirable gas transport properties. However, PAs containing 1,1,1,3,3,3-hexa luoro-2,2-diphenylpro-pane exhibited higher gas permeability coefficients and modestly lower gas separation factors. 

As shown in Scheme 6.81, this synthetic methodology has been successfully applied to the synthesis of various carbaporphyrinoids with pyridine 331 [190], indene 332 [178, 191], azulene 333 [192], and the related subunits 334 [193] and 335 [191] as components of the conjugated macrocycle [194-197]. The azuleneporphyrins 333 was prepared by the reaction of 1,3-diformylazulene as a stable compound by Lash and coworkers. But, under different conditions, 336, involving an indene moiety, is produced. The authors conclude that 333 shows aromatic character due to zwitterionic canonical forms such as 333B [192]. 

Notably, the indene moiety of the [2 + 2 + 2] cycloaddition product 91 now served as the dienophile, and the o-quinone moiety of 92 provided the heterodiene unit in this brilliant example of an intramolecular hetero-Diels-Alder reaction. Nine more steps were then required to transform the polycycle 93 into sporolide B (94). 

These results ultimately suggested that polymer-solvent and polymer- lymer interactions could be modulated by shifting the attachment point used for the covalent conjugation between the MOEG chain and the indene moiety. 

By the contrast, the polymer bearing a hydrogen atom at the 2-position of the indene moiety (poly-BF3a) failed to show any significant depolymerization after... 

The comparison of the C-NMR spectra of BFl, 1,2-model, and 1,4-model suggested that the signal attribntable to the carbon atom of the pendent phenyl bonded to the indene moiety (C-T, Fig. 24) showed a chemical shift almost equal in BFl and 1,2-model (131.5 and 131.6 ppm, respectively), while the C-T signal of 1,4-model was downfleld shifted at 136.5 ppm and no signals were present in the region of the spectrum between 130 and 135 ppm. This observation was explained by the fact that C-T is bonded to unsaturated C-3 atoms in both BFl and 1,2-model, while in the 1,4-model the double bond is shifted and C-T is linked to a satnrated C-3 atom. 

In order to define if the stereoelectronic nature and/or the steric hindrance of the substituents present on the indene moieties affects the polymer microstructure, different Ri, R2, and R3 substituted benzofulvene derivatives were prepared and submitted to a comprehensive NMR study ( H, C, and HSQC experiments on the whole set of the polymers) [22],... 

Number of -NMR signals attributable to aliphatic quaternary carbon at the 1-position of the indene moiety... 

The analysis of the chemical shift values and NOESY spectra of dimers provided important information about the tendency to accommodate their bicycUc moiety in an antiparallel stacked orientation (Figs. 26 and 27). This observation was considered to be very important for Dimer-l -l -Major in which the tetrahedral geometry of both the indene C-1 atoms appeared to force the indene moieties to stack... 

The cross-peaks observed in the NOESY spectrum for the methyl protons of the ethyl group of Dimer-l,2-l,2-Major were considered to be diagnostic. In particular, A-bfl and A-bf2 protons showed symmetric intra- and inter-residue cross-peaks. Namely, H-A-fc/1 interacted with both R-2 l6 -bfl and H-375 -(i/l (intra-residue) and with H-6-fc/2 and M-l-bfl (inter-residue) and H-A-fc/2 interacted with H-276 -bfl and H-375 -fc/2 (intra-residue) and with H-6-(>/l and H-l-bfl (inter-residue). Overall, aU these observations supported the hypothesis of an antiparallel stacked orientation of indene moieties of Dimer-l,2-l,2-Major with a further stabilization due to symmetric (pendant)phenylindene interactions. 

The polybenzofulvene derivatives bearing an ester group in position 2 of the indene moiety (e.g., poly-BFl, poly-BF3k) have been found to show intense emission bands around 440-460 nm (see Table 9 of Absorption and Emission Spectroscopy section), whereas the presence of snbstituents different from the COOR was found to decrease significantly the emission intensity (Fig. 54). This result complicated the study and the eventual exploitation of the emission properties of poly-BF3 derivatives... 

Such copolymers of oxygen have been prepared from styrene, a-methylstyrene, indene, ketenes, butadiene, isoprene, l,l-diphen5iethylene, methyl methacrjiate, methyl acrylate, acrylonitrile, and vinyl chloride (44,66,109). 1,3-Dienes, such as butadiene, yield randomly distributed 1,2- and 1,4-copolymers. Oxygen pressure and olefin stmcture are important factors in these reactions for example, other products, eg, carbonyl compounds, epoxides, etc, can form at low oxygen pressures. Polymers possessing dialkyl peroxide moieties in the polymer backbone have also been prepared by base-catalyzed condensations of di(hydroxy-/ f2 -alkyl) peroxides with dibasic acid chlorides or bis(chloroformates) (110). 

When the ring system containing the sulfone moiety is unsaturated, a quite different set of products has been observed on photolysis, apparently arising from an initial cycloreversion to a short-lived sulfene intermediate. For example, irradiation of 2H-1-benzothiopyran 1,1-dioxide (41) in dichloromethane or methanol gave the cis- and trans-sultines (42) and the ring-expanded sultine (43) in roughly equal amounts, accompanied by minor amounts ( 5%) of the products of formal loss of S02, i.e. indene, and SO, i.e. 4472... 

This sequence has been successfully extended to the regioselective multicomponent construction of bis- pyrano-l,4-benzoquinone derivatives when unsubstituted 2,5-dihydroxy-l,4-benzoquinone is used (Scheme 39) [130], Depending on the alkene moiety, the reaction yielded only the linear tri-, penta-, or heptacyclic product in a 1 1 diasteromeric ratio, as illustrated with indene. 

As part of a preparation of marine odourants, oxidation by RuCyaq. Na(lO )/ CCl of the =CH3 moiety in the marine floral-aldehyde 1-methyl-7-methylene-2,3,7,8-tetrahydro-l//,6//-5,9-dioxacyclohepta[/]indene gave l-methyl-2,3-di-hydro-l//-5,9-dioxa-cyclohepta[/]-inden-7-one (Fig. 3.16) [200]. 

Danopoulos and co-workers reported on the preparation of NHC ligands with pendant indenyl and fluorenyl groups.19 Deprotonation of the alkyl -indene or -fluorene imidazolium salts with one equivalent of potassium hexamethyldisilazide leads to NHCs functionalised with neutral indene or fluorene moieties (IndH-NHC and F1H-NHC). Further deprotonation with... 

The research team of D.F. Covey developed a synthetic route to convert 5p-methyl-3-ketosteroids into 7(S)-methyl substituted analogues of neuroactive benz[e]indenes. The synthesis began with 19-nortestosterone, in which the a,p-unsaturated cyclic ketone moiety was degraded to afford a tricyclic aldehyde. This aldehyde was unstable and could not be stored. For this reason it was immediately subjected to the Tsuji-Wllkinson decarbonylation to afford the decarbonylated product in high yield. 

Based on the cyclic-blocking moieties and other substituent groups, subtype-selective muscarinic antagonists can be classified into eight groups (l)tricyclic benzodiazepines, (2) benzothiazepines, (3) quinuclidines, (4) poly-methylene tetramines, (5)indenes, ( 6)sila-difenidols, (7) diphenylacetyloxy derivatives, and (.8) himbacine akaloids. 

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