91925-45-0

Upstream product

• 32651-20-0 1,4-diphenylcyclohexane-1,4-diol 
• 21113-62-2 1,4-diphenyl-1,3-cyclohexadiene 

Downstream Products

• 21113-62-2 1,4-diphenyl-1,3-cyclohexadiene 
• 123207-76-1 syn-1,2;3,4-bis(epoxy)-1,4-diphenylcyclohexane 
• 92-94-4 [1,1';4',1'']terphenyl 
• 1366368-88-8 (+/-)-2-hydroxy-5-oxo-2,5-diphenylpentanal 
• 495-71-6 phenacylacetophenone 
• 114396-00-8 1,4-Diphenyl-2,3-dioxa-bicyclo[2.2.2]octane 
• 1029698-31-4 1,4-diphenyl-cyclohex-2-ene-cis-1,4-diol 

Relevant academic research and scientific papers

Ozonolysis of bicyclic 1,2-dioxines: Initial scope and mechanistic insights

The ozonolysis of bicyclic 1,2-dioxines was investigated using a variety of 1,4-disubstituted 1,2-dioxines along with a 1,3-dialkyl and steroidal example, with yields ranging from moderate to excellent. Two different pathways were observed upon reaction of the 1,4-disubstituted 1,2-dioxines with ozone; one pathway saw the "expected" results, that is, cleavage of the olefinic moiety with generation of 1,4-dicarbonyl 1,2-dioxines, while the other pathway revealed a previously unobserved rearrangement involving cleavage of the peroxide linkage along with loss of either CO or CO2. Several unsymmetrical ozonolyses were also performed to further investigate the origins of this rearrangement, and initial mechanistic insights into the fragmentation pathways are discussed.

Synthesis and chemistry of 2,3-dioxabicyclo[2.2.2]octane-5,6-diols

(Chemical Equation Presented) 1,4-Disubstituted 2,3-dioxabicyclo[2.2.2]oct- 5-enes were dihydroxylated with osmium tetroxide to yield diols anti to the peroxide linkage in a highly selective manner. Reduction of the peroxide bond furnished cyclohexane-1,2,3,4-tetraols with toxocarol relative stereochemistry in excellent yield. This new methodology was employed to synthesize the natural product (1S,2R,3S,4R,5R)-2-methyl-5-(propan-2-yl)cyclohexane-1,2,3,4-tetrol (1) in a short sequence from (R)-α-phellandrene. Moreover, during the study of the chemistry of 2,3-dioxabicyclo[2.2.2]octane-5,6-diols a hitherto unknown rearrangement was discovered which has wide applicability for the synthesis of 1,4-dicarbonyls, including optically enriched synthons. A broad range of mechanistic investigations applicable to this rearrangement are also reported.

A radical-anion chain mechanism initiated by dissociative electron transfer to a bicyclic endoperoxide: Insight into the fragmentation chemistry of neutral biradicals and distonic radical anions

The electron-transfer (ET) reduction of two diphenyl-substituted bicyclic endoperoxides was studied in N,N-dimethylformamide by heterogeneous electrochemical techniques. The study provides insight into the structural parameters that affect the reduction mechanism of the 0-0 bond and dictate the reactivity of distonic radical anions, in addition to evaluating previously unknown thermochemical parameters. Notably, the standard reduction potentials and the bond dissociation energies (BDEs) were evaluated to be -0.55 ±0.15 V and 20±3 kcal mol-1, respectively, the last representing some of the lowest BDEs ever reported. The endoperoxides react by concerted dissociative electron transfer (DET) reduction of the 0-0 bond yielding a distonic radical-anion intermediate. The reduction of 1,4-diphenyl-2,3-dioxabicyclo[2.2.2]oct-5-ene (1) results in the quantitative formation of 1,4-diphenylcyclohex-2-ene-c/s-1,4-diol by an overall two-electron mechanism. In contrast, ET to 1,4-diphenyl-2,3-dioxabicyclo[2.2.2]octane (2) yields 1,4-diphenylcyclohexane-c/s-1,4-diol as the major product; however, in competition with the second ET from the electrode, the distonic radical anion undergoes a β-scission fragmentation yielding 1,4-diphenyl-1,4-butanedione radical anion and ethylene in a mechanism involving less than one electron. These observations are rationalized by an unprecedented catalytic radical-anion chain mechanism, the first ever reported for a bicyclic endoperoxide. The product ratios and the efficiency of the catalytic mechanism are dependent on the electrode potential and the concentration of weak non-nucleophilic acid. A thermochemical cycle for calculating the driving force for β-scission fragmentation is presented, and provides insight into why the fragmentation chemistry of distonic radical anions is different from analogous neutral biradicals.

Lewis acid catalysed rearrangements of unsaturated bicyclic [2.2.n] endoperoxides in the presence of vinyl silanes; access to novel Fenozan BO-7 analogues

Reactions of a series of unsaturated bicyclic [2.2.n] endoperoxides with allyltrimethylsilane in the presence TMSOTf or SnCl4 provides the cis-configured endoperoxides 9a-12. It is proposed that this novel reaction proceeds via attack of the al

Synthesis of polycyclic 1,2-dioxanes from endoperoxides

1,4-Diphenylcyclohex-2-ene 1,4-endoperoxide (7) on catalysis with trimethylsilyl trifluoromethanesulfonate (TMSOTf) in CH2Cl2 at -78°C reacted partially with 1,4-diphenylcyclopenta-1,3-diene (5) to give 3a,5a,6,7,9a,9b-hexahydro-2,5a

The Diastereoselective Formation of 1,2,4-Trioxanes and 1,3-Dioxolanes by the Reaction of Endoperoxides with Chiral Cyclohexanones

1,4-Diphenyl-2,3-dioxabicyclo[2.2.1]hept-5-ene (2), on treatment with a catalytic amount of trimethylsilyl trifluoromethanesulfonate (Me3SiOTf) in CH2Cl2 at -78°, reacts with excess (-)-menthone (10) to give (1S,2S,4′aS,5R,7′aS)-4′a,7′a-dihydro-2-isopropyl-5- methyl-6′,7′-diphenylspiro[cyclohexane-1,3′-[7′H] cyclopenta-[1,2,4]trioxine] (11) and its (1R,2S,4′aS,5R,7′aS)-diastereoisomer 12 in a 1:1 ratio and in 21% yield. Repeating the reaction with 1.1 equiv, of Me3SiOTf with respect to 2 affords 11, 12, and (1S,2S,3′aR,5R,6′aS)-3′a,6′a-dihydro-2-isopropyl-5- methyl-3′a-phenoxy-5′-phenylspiro[cyclohexane-1,2′-[4′H] cyclopenta[1,3]dioxole] (13) together with its (1R,2S,3′aS,5R,6′aR)-diastereoisomer 14 in a ratio of 3:3:3:1 and in 56% yield. (+)-Nopinone (15) in excess reacts with 2 in the presence of 1.1 equiv. of Me3SiOTf to give a pair of 1,2,4-trioxanes (16 and 17) analogous to 11 and 12, and a pair of 1,3-dioxolanes (18 and 19) analogous to 13 and 14, in a ratio of 8:2:3:3 and in 85% yield. (-)-Carvone and racemic 2-(tert-butyl)cyclohexanone under the same conditions behave like 15 and deliver pairs of diastereoisomeric trioxanes and dioxolanes. In general, catalytic amounts of Me3SiOTf give rise to trioxanes, whereas 1.5 equiv. overwhelmingly engender dioxolanes. Adamantan-2-one combines with 2 giving only (4′aRS,7′aRS)-4′a,7′a-dihydro-6′,7′a- diphenylspiro[adamantane-2,3′-[7′H]cyclopenta[1,2,4]trioxine] in 98% yield regardless of the amount of Me3SiOTf used. The reaction of 1,4-diphenyl-2,3-dioxabicyclo[2.2.2]oct-5-ene (32) with 10 and 1.1 equiv. of Me3SiOTf produces only the pair of trioxanes 33 and 34 homologous to 11 and 12. Treatment of the (S,S)-diastereoisomer 33 with Zn and AcOH furnishes (1S,2S)-1,4-diphenylcyclohex-3-ene-1,2-diol. The crystal structures of 11-13 and 16 are obtained by X-ray analysis. The reaction courses of 10 and the other chiral cyclohexanones with prochiral endoperoxides 2 and 32 to give trioxanes are rationalized in terms of the respective enantiomeric silylperoxy cations which are completely differentiated by the si and re faces of the ketone function. The origin of the 1,3-dioxolanes is ascribed to 1,2 rearrangement of the corresponding trioxanes, which occurs with retention of configuration of the angular substituent.

Antimalarially potent, easily prepared, fluorinated endoperoxides

Three or four step chemical synthesis and in vitro antimalarial testing showed crystalline, thermally stable, bicyclic endoperoxides 3c and 4c to be potent antimalarials, having approximately 15% of the antimalarial activity of the clinically used, comple

Electron-transfer Photochemistry of Endoperoxides

Derivatives of 1,2-dioxacyclohex-4-ene and 2,3-dioxabicyclooct-5-ene (endoperoxides, EPs) form EDA complexes with tetracyanoethylene (TCNE).The phenyl-substituted EPs 3a, 4a, 4b and 6 undergo electron-transfer-induced reactions when the EDA complexes are irradiated.Two types of reactions are observed depending on the ring system.Monocyclic EPs (3a, 4a and 4b) afford furan derivatives, possibly through the Criegee-type rearrangement, and dehydration, whereas the bicyclic EP 6 undergoes cycloreversion through the C-O bond cleavage.

Ruthenium(II)-Catalyzed Reactions of 1,4-Epiperoxides

The behavior of 1,4-epiperoxides in the presence of transition-metal complexes is highly dependent on the structures of the substrates and the nature of the metal catalysts.Reaction of saturated epiperoxides such as 1,3-epiperoxycyclopentane, 1,4-epiperoxycyclohexane, or dihydroascaridole catalyzed by RuCl2(PPh3)3 in dichloromethane gives a mixture of products arising from fragmentation, rearrangement, reduction, disproportionation, etc.Prostaglandin H2 methyl ester undergoes clean and stereospecific fragmentation to afford methyl(5Z,8E,10E,12S)-12-hydroxy-5,8,10-heptadecatrienoate and malonaldehyde.Bicyclic 2,3-didehydro 1,4-epiperoxides give the syn-1,2:3,4-diepoxides by the same catalyst.The monocyclic analogues are transformed to a mixture of diepoxides and furan products.The stereochemical outcome of the epoxide formation reflects unique differences in the ground-state geometry of the starting epiperoxide substrates.FeCl2(PPh3)2 serves as a useful catalyst for the skeletal change of sterically hindered bicyclic 2,3-didehydro 1,4-epiperoxides to the syn-diepoxides.In addition, the Fe complex best effects the conversion of 1,4-unsubstituted 2,3-didehydro epiperoxides to furans.The Ru-catalyzed reactions are interpreted in terms of the intermediacy of inner-sphere radicals formed by atom transfer of the Ru(II) species to peroxy substrates, in contrast to the Fe-catalyzed reactions proceeding via free, outer-sphere radicals generated by an electron-transfer mechanism.