Cyclohexanol, 2,2,6,6-tetrakis

Chemical Name Cyclohexanol-2,2,6,6-tetrakis(hydroxymethyl)tetranicotinate... 

The formation of ethers such as 1806 by EtsSiH 84b can also be catalyzed by trityl perchlorate to convert, e.g., benzaldehyde in 84% yield into dibenzyl ether 1817 [48]. The combination of methyl phenethyl ketone 1813 with O-silylated 3-phenyl-n-pro-panol 1818, in the presence of trityl perchlorate, leads to the mixed ether 1819 in 68% yield [48] (Scheme 12.15). Instead of trityl perchlorate, the combination of trityl chloride with MesSiH 84a or EtsSiH 84b and sodium tetrakis[3,5-bis-(trifluoro-methyl)phenyl]borane as catalyst reduces carbonyl groups to ethers or olefins [49]. Employing TMSOTf 20 as catalyst gives very high yields of ethers. Thus benzaldehyde reacts with O-silylated allyl alcohol or O-silylated cyclohexanol to give the... 

Groves et al. found that a simple heme-iodosobenzene system mimics the enzymic reactions.127 Cyclohexane and cyclohexene are oxidized to cyclohexanol and a mixture of cyclohexene oxide and cyclohexenol respectively by this system. Using meso-tetrakis-a,/J,a,/J-(o-acylamidophenyl)por-phinatoiron(III) chloride where the acyl group is (i )-2-phenylpropionyl or (S)-2 -methoxy-carbonyl-l,T-binaphthyl-2-carbonyl, optically active styrene oxides are obtained in 51% e.e. The Fe(TPP)Cl-PhIO system can also oxygenate arenes to arene oxides.128 Based on the following observations, mechanisms involving O—Felv(Por) t as the active species have been proposed (Scheme 30).127... 

Polyols with a large number of terminal hydroxyl groups result when the reaction is initiated with compounds such as pentaerythritol, 2,2,6,6-tetrakis(hydroxymethyl) cyclohexanol, or with natural products, for example, sucrose, raffinose, or D-mannitol. Amines such as ethylenediamine, diethylenetriamine, and 2,4-diaminotoluene may also be used as the active hydrogen-containing initiator. 

Koda and coworkers (249) have reported the air oxidation of cyclohexane in SCCO2 to yield cyclohexanol and cyclohexanone in the presence of an iron porphyrin catalyst containing the mera-pentafluorophenyl group [FeCl(TPFPP), where TPFPP = 5,10,15,20-tetrakis(pentafiuorophenyl)porphyrin]. The pentaflu-orophenyl groups were believed to enhance the catalyst solubility in the SCCO2 phase, although the solubility was not measured. The reaction required essentially stoichiometric quantities of acetaldehyde (250). The total yield of cyclohexanol and cyclohexanone was reported as 5% for 1 h reaction time at 70 C and 90 bar, which corresponded to a turnover number of 100. Selectivity to cyclohexanol and cyclohexanone was approximately equivalent at all conditions studied. 

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