Indene epoxide

Research groups at Sepracor53 54 and Merck50-52 independently developed similar strategies to access (lS)-amino-(2R)-indanol. Both processes used Jacobsen s Mn-(salen) catalyst (MnLCl, 2g)42-44,55 for indene epoxidation, followed by chirality transfer of the C-0 bond of indene oxide 26 to obtain enantiopure (15)-amino-(2/f)-indanol (Scheme 24.2). 

Jerina e( al. (1968) have shown that an epoxide hydrase of rabbit liver microsomes, or the. soluble fraction of liver homogenate, convert benzene epoxide to the dihydrodiol (see Fig. 4). The reaction was also demonstrated with styrene epoxide, indene epoxide, and cyclohexene epoxide. A soluble dehydrogenase from the liver preparation oxidized dihydrodiols to catecliols. The conversion of the epoxide to phenol was considered to be a nonenzymic isomerization. In the presence of glutathione and glutathione-iS-epoxide transferase, a glutathione conjugate was formed. 

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). 

Oxaziridines unsubstituted at nitrogen as well as some iV-acylated oxaziridines offer synthetic potentialities due to their ability to transfer their nitrogen function to nucleophiles (Section 5.08.3.1.4). The simplicity of preparation of some aziridines from alkenes and the Spiro oxaziridine (S2) equals the simplicity of epoxidation. Aziridine (299), for example, is obtained by simple heating of indene with (52) in toluene (74KGS1629). 

The epoxidation method developed by Noyori was subsequently applied to the direct formation of dicarboxylic acids from olefins [55], Cyclohexene was oxidized to adipic acid in 93% yield with the tungstate/ammonium bisulfate system and 4 equivalents of hydrogen peroxide. The selectivity problem associated with the Noyori method was circumvented to a certain degree by the improvements introduced by Jacobs and coworkers [56]. Additional amounts of (aminomethyl)phos-phonic acid and Na2W04 were introduced into the standard catalytic mixture, and the pH of the reaction media was adjusted to 4.2-5 with aqueous NaOH. These changes allowed for the formation of epoxides from ot-pinene, 1 -phenyl- 1-cyclohex-ene, and indene, with high levels of conversion and good selectivity (Scheme 6.3). 

Compounds lb and 2b were the Urst fluorinated ligands tested in Mn-catalyzed alkene epoxidation [5,6]. The biphasic Uquid system perfluorooc-tane/dichloromethane led to excellent activity and enantioselectivity (90% ee) in the epoxidation of indene with oxygen and pivalaldehyde (Scheme 1, Table 1). In addition, the fluorous solution of the catalyst was reused once and showed the same activity and selectivity. This represents a considerable improvement over the behavior in the homogeneous phase, where the used catalyst was bleached and reuse was impossible. Unfortunately, indene was the only suitable substrate for this system, which failed to epoxidize other alkenes (such as styrene or 1,2-dihydronaphthalene) with high enantioselectivity. The system was also strongly dependent on the oxidant and only 71% ee was obtained in the epoxidation of indene with mCPBA at - 50 °C. 

Asymmetric epoxidation of indene as a step in making the HIV Davies and Reider... 

Davies and Reider (1996) have given some details of the HIV protease inhibitor CRDCIVAN (INDINAVIR) for which (lS,2R)-c -amino indanol is required. Indene is epoxidized enantioselectively, using the lacobsen strategy (SS-salen Mn catalyst, aqueous NaOH and PiNO), to (lS,2/ )-indene oxide in a two-phase system, in which the OH concentration is controlled. Indene oxide was subjected to the Ritter reaction with MeCN, in the presence of oleum, and subsequent hydrolysis and crystallization in the presence of tartaric acid gives the desired amino indanol. 

More subtle arguments have been invoked to rationalize the dichotomous behavior of so-called second-generation Mn-salen catalysts of type 7 toward unfunctionalized and nucleophilic olefins. For example, higher yields and ee s are obtained with the (i ,S)-complex for the epoxidation of indene (8). However, JV-toluenesulfonyl-l,2,3,4-tetrahydropyridine (10) gave better results using the (R,/ -configuration. An analysis of the transition-state enthalpy and entropy terms indicates that the selectivity in the former reaction is enthalpy driven, while the latter result reflects a combination of enthalpy and entropy factors <00TL7053>. 

A typical manganese-salen complex (27)[89] is capable of catalysing the asymmetric epoxidation of (Z)-alkenes (Scheme 18) using sodium hypochlorite (NaOCl) as the principle oxidant. Cyclic alkenes and a, (3-unsaturated esters are also excellent starting materials for example indene may be transformed into the corresponding epoxide (28) with good enantiomeric excess1901. The epoxidation of such alkenes can be improved by the addition of ammonium acetate to the catalyst system 911. 

Bromine-atom atomic resonance absorption spectrometry (ARAS) has been applied to measure the thermal decomposition rate constants of CF3Br in Kr over the temperature range 1222-1624 K. The results were found to be consistent with recently published theory. The formation of cyclopent[a]indene and acenaphthylene from alkyl esters of biphenyl-mono- and -di-carboxylic acids has been observed in flash vacuum pyrolyses at 1000-1100 °C. The kinetics and mechanisms of free-radical generation in the ternary system containing styrene epoxide, / -TsOH, and i-PrOH have been examined in both the presence and absence of O2. ... 

Synonyms AI3-25584 EINECS 213-831-0 ENT 25584 Epoxy heptachlor HCE HE (3-Heptachlor epoxide Heptachloro epoxide l,4,5,6,7,8,8-Heptachloro-2,3-epoxy-2,3,3a,4JJa-hexahydro-4,7-methanoindene l,2,3,4,5,6,7,8,8-Heptachloro-2,3-epoxy-3a,4,7,7a-tetrahydro-4,7-methanoindene 5a,6,6a-Hexahydro-2,5-methano-2/f-indeno[l,2-A]oxirene 2,3,4,5,6,7,7 Hep tachloro-la,lb,5,5a,6,6a-hexahydro-2,5-methano-2//-oxireno[a]indene UN 2761 Velsicol 53-CS-17. 

Heptachloro-la, lb,5,5a,6.6a-hexahydro-2,5-methano-27/-oxireno[a]indene, see Heptachlor epoxide... 

Heptachloro-3a,4,7,7a-tetrahydro-4,7-methano-l/7-indene see Chlordane Heptachlor triol, see Heptachlor epoxide Heptanal, see Heptane. 1-Octene 1-Fleptanol. see Heptane Heptanoic acid, see Heptane 1-Fleptene. see Heptane Heptyl hydroperoxide, see Heptane Hexachlorobenzene, see Hexachlorobutadiene,... 

For 2,2-disubstituted epoxides 68a-d bearing a 2-phenyl substituent, their corresponding catalytic cyclizations gave good yields of l-phenyl-2-methyl-lH- indenes 69a-c using the same ruthenium catalyst under similar conditions [25]. It is interesting to note that the same product 69c vas obtained for different epoxides 68c and 68d, bearing a fiuoro substituent at their phenyl C4 and C5, respectively. 

Enantiomerically pure epoxides and diols, readily available through the asymmetric epoxidation and asymmetric dihydroxylation reactions, are ideal precursors to prepare cis-amino alcohols via the Ritter reaction. " " A Merck group has shown that indene oxide 175a can be converted effectively to c/i-l-amino-2-indanol, a key fragment of the HlV-protease inhibitor Indinavir via the cis-... 

A one-step synthesis of isochromene itself has been reported from indene oxide (191) (66CC415). Irradiation of the epoxide in benzene affords two products, isochromene and indan-2-one, in similar quantities. It was proposed that initial fission of the carbon-carbon bond of the three-membered ring is followed by 1,4- or 1,2-hydrogen migration (Scheme 36). 

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