29903-57-9

Upstream product

• 90-47-1 xanth-9-one 
• 6749-78-6 4-methylphenylmagnesium iodide 
• 4294-57-9 para-methylphenylmagnesium bromide 
• 106-38-7 para-bromotoluene 

Downstream Products

• 29903-63-7 9-(4-methylphenyl)-9H-xanthene 
• 53829-30-4 9-(p-Methylphenyl)xanthyl 
• 136345-35-2 9-Chloro-9-(4-methylphenyl)xanthene 
• 103019-25-6 bis-(9-p-tolyl-xanthen-9-yl)-peroxide 
• 136345-27-2 5'-O-<9-(4-Methylphenyl)xanthen-9-yl>thymidine 
• 191168-41-9 9-hydroxy-9-(4-carboxyphenyl)xanthene 

Relevant academic research and scientific papers

A Sc(OTf)3 catalyzed dehydrogenative reaction of electron-rich (hetero)aryl nucleophiles with 9-aryl-fluoren-9-ols

A highly efficient dehydrogenative reaction of a series of nucleophiles with 9-aryl-fluoren-9-ols has been realized by using only 2 mol% of Sc(OTf)3 as a catalyst. The corresponding indole-containing 9,9-diarylfluorenes were obtained in up to 99% yield as well as other electron-rich (hetero)arene adducts. The protocol exhibits high selectivity, mild reaction conditions and good substrate compatibility (32 examples). This protocol is further highlighted by its applications in the construction of potential electroluminescent materials.

p-Quinoid compounds by nucleophilic aromatic substitution with hydride as leaving group

Triarylmethylium tetrafluoroborates with a sterically shielded cationic center react with selected C- and N-nucleophiles under nucleophilic aromatic substitution to give dipolar p-quinoid final products. The mechanistic rationale includes a hydride leavin

9-Phenylxanthen-9-ylium and 9-phenylthioxanthen-9-ylium ions: Comparison of o- and p-substitutions in the 9-phenyl group by cyclic voltammetry and visible spectra

9-Arylxanthen-9-ylium (3a-i) and 9-arylthioxanthen-9-ylium (4a,b,e-i) perchlorates [aryl = 2,4,6-(MeO)3C6H2 (a), 2,6-(MeO)2C6H3 (b), 2-MeOC6H4 (c), 4-MeOC6H4 (d), 3-Br-2,6-(MeO)2C6H2 (e), 2,4,6-Me3C6H2 (f), 2-MeC6H4 (g), 4-MeC6H4 (h), C6H5 (i)] were prepared by the reactions of 9-arylxanthen-9-ols or 9-arylthioxanthen-9-ols with perchloric acid. Their LUMO and HOMO levels were estimated from the redox potential (E0) in cyclic voltammetry and λmax in the UV-visible spectra measured for a 1,2-dichloroethane solution, and were compared with those of 9-aryl-1,8-dimethoxyxanthen-9-ylium ions (8b,i). We found that 1) both the LUMO and HOMO levels varied almost in the same order of substituent on the 9-phenyl group; 2) the MeO-group on the 9-phenyl group was more effective to raise both the HOMO and LUMO levels than the Me-group; 3) the HOMO levels of 3 and 4 were more sensitive than the LUMO levels to the change in the 9-aryl group; 4) p-substitution by MeO- or Me-groups was more effective to raise the HOMO and LUMO levels than o-substitution; 5) the presence of two o-MeO groups was more effective to raise the HOMO and LUMO levels than one o-MeO group; 6) a m-bromination of 9-aryl group in 3b or 4b greatly lowered both LUMO and HOMO levels, as observed for 3e or 4e; 7) both the HOMO and LUMO levels of 8b and 8i were higher than those of 3b and 3i, respectively; 8) the LUMO level of 3b was higher than that of 8i, the isomer.

Tricylic amino-acid derivatives

Described herein are compounds which have the general formula: or a prodrug or pharmaceutically acceptable salt, solvate or hydrate thereof wherein: R1 is selected from the group consisting of H, alkyl and the counter ion for a basic addition salt; X is selected from the group consisting of CR9R10, S, O, SO, SO2, NH and N-alkyl; R2, R3, R4, R9 and R10 are independently selected from the group consisting of H and alkyl; R5 and R6 are independently selected from the group consisting of H, alkyl and phenyl, or, alternatively, R5 and R6 together may form a methylene group or a 3- to 6-membered a spirocyclic group; wherein, when X is CR9R10, one or both pairs of R5 and R9 or R6 and R10 may join to form a double or triple bond R7 is selected from the group consisting of Formula II-V: which are all optionally substituted, at nodes other than R8, with 1-4 substituents independently selected from the group consisting of alkyl, halo, aryl (which may be substituted as for R8), trifluoromethyl, trifluoromethoxy, nitro, cyano, amino, mono-alkylamino, di-alkylamino, alkoxycarbonyl, alkylcarbonyl, alkoxythiocarbonyl, alkylthiocarbonyl, alkoxy, alkylS-, phenoxy, -SO2NH2, -SO2NHalkyl, -SO2N(alkyl)2 and 1,2-methylenedioxy; and wherein any of the benzo-fused rings in structures II to V may be replaced by a 5- or 6-membered heterocyclic ring selected from the group consisting of pyridine, thiophene, furan and pyrrole; wherein R8 is selected from the group consisting of H, alkyl, benzyl, cycloalkyl, indanyl and an optionally substituted aryl group, wherein the optional substituents are independently selected from 1-4 members of the group consisting of alkyl, halo, aryl, trifluoromethyl, trifluoromethoxy, nitro, cyano, amino, mono-alkylamino, di-alkylamino, alkoxycarbonyl, alkylcarbonyl, alkoxythiocarbonyl, alkylthiocarbonyl, alkoxy, alkylS-, phenoxy, -SO2NH2, -SO2NHalkyl, -SO2N(alkyl)2 and 1,2-methylenedioxy; -represents a single or double bond; Y is selected from the group consisting of O, S, SO, NH, N-alkyl, CH2, CH-alkyl, C(alkyl)2, and C=O; Z is selected from the group consisting of CH2, O, S, NH and N-alkyl when-is a single bond; Z is selected from the group consisting of CH and N when-is a double bond. Also described is the use of these compounds as pharmaceuticals.

9-Hydroxy-9-(4-carboxyphenyl)xanthene - A new linker for the synthesis of peptide amides

The easy synthesis of 9-hydroxy-9-(4-carboxyphenyl)xanthene 1 a new linker for the solid phase peptide synthesis of peptide amides is reported. The cleavage conditions were checked and several peptide amides were synthesized using the TentaGel-resin(TM) o

Triarylmethanes and 9-arylxanthenes as prototypes amphihydric compounds for relating the stabilities of cations, anions and radicals by C-H bond cleavage and electron transfer

Thermodynamic stability properties of 11 p-substituted trityl and seven 9-phenylxanthyl carbocations are reported in sulfolane and of their conjugate carbanions in DMSO. The cations are compared by calorimetric heats of hydride transfer from cyanoborohydride ion, their first and second reduction potentials, their pK+Rs in aqueous sulfuric acid, 13C chemical shifts and free energies of methoxy exchange. Carbanions are compared by their heats and free energies (pKHA) of deprotonation and their first and second oxidation potentials. Radicals are compared by their oxidation and reduction potentials. Their bond dissociation energies are derived by alternative routes: from the carbocation and its reduction potential and from the carbanion and its oxidation potential. The various properties are correlated against each other and against appropriate Hammett-type substituent parameters. Correlations between the different measured properties reported here range from fair to excellent. Despite their importance as historic prototypes for the three trivalent oxidation states of carbon, trityl and xanthyl systems are atypical models for comparing transmission of electron demand in other series of carbocations, radicals or carbanions with significantly different structures. The 9-arylxanthyl series is especially poor because of its insensitivity to substituent effects. The effects of substituents on various properties which represent the stabilities of R+s correlate surprisingly well against those for corresponding R-s. Accordingly, compensating effects on the oxidation and reduction of a series of related R.s may lead to a nearly constant electron transfer energy and absolute hardness for the series. In contrast, the free energies for interconversion of the carbocations and carbanions which determine the gap between pKR+. and pKHA are very sensitive to structural change.

Quenching Behavior of Singlet Excited 9-Arylxanthylium Cations

Several 9-arylxanthylium tetrafluoroborate salts (Ar=H, p,m-F, p,m-Me, m-OMe) were synthesized by reaction of the corresponding 9-arylxanthen-9-ol with fluoroboric acid.Spectral characteristics of the xanthyl cations were identical to those previously rep

Some Substituted 9-Phenylxanthen-9-yl Protecting Groups

Xanthen-9-one 8 was converted into 9-(4-methoxyphenyl)-, 9-(4-methylphenyl)- and 9--xanthen-9-ol (10; R1 = OMe, R2 = H, 10; R1 = Me, R2 = H, and 10; R1 = H, R2 = CF3, respectively).The corresponding 5'-protected thymidine derivatives (13; R1 = OMe, R2 = H, 13; R1 = Me, R2 = H and 13; R1 = H, R2 = CF3) were obtained in satisfactory yields from thymidine 12 and the appropriate 9-chloro compounds (11; R1 = OMe, R2 = H, 11; R1 = Me, R2 = H and 11; R1 = H, R2 = CF3).In the same way, 2,7-dibromoxanthen-9-one 14 was converted into two 9-aryl-2,7-dibromoxanthen-9-ols ( compounds 15a and 15b).Reaction between thymidine 12 and the corresponding 9-chlorocompounds gave the 5'-protected thymidine derivatives 16a and 16b, also in satisfactory yields.The rates of acid-catalysed cleavage of the above five 5'-protected thymidine derivatives (13; R1 = OMe, R2 = H, 13; R1 = Me, R2 = H and 13; R1 = H, R2 = CF3), 16a and 16b were compared with those of 5'-O-(9-phenylxanthen-9-yl)thymidine 13; R1 = R2 = H and 5'-O-(triphenylmethyl)thymidine 3a; B = thymin-1-yl under the same conditions.

Electrophilic Reactions of Xanthylium Carbocations Produced by Flash Photolysis of 9-Xanthenols

The xanthylium ion and eight 9-aryl derivatives (p-MeO, p-Me, m-Me, H, p-F, m-MeO, p-Cl, and p-CF3 phenyl) were produced in 1:4 acetonitrile/water by flash photolysis of the corresponding 9-xanthenols.The identifications of the transients as xanthylium ca