The average molecular weight of the reduced pyridine-soluble material decreases with increase in rank of the coal. Coking properties of these coals can be related to proportions of material in the two modes of distribution of molecular weight....
To a solution of N(N)dialkylaniline(1 mmol) in tBuOH(1 mL)was added CuCl(1 mg)and TBHP(330 --- *Corresponding author E,mail: cjxi@tsinghua edu cn Received December 8,2008;accepted February 14,2009 Supported by the National Natural Science Foundation of China(No 20572058)862 CHEM RES ...
PCC, CH2Cl2 t-Bu2FSi R t-Bu2FSi t-Bu2FSi 11a, b 10a, b 9a, b KMnO4, CH2Cl2, t-BuOH, NaH2PO4/H3PO4, O OH OMe a: R = H b: R = OMe TBDMS = t-BuMe2Si PCC = (C5H6N)+(CrClO 3)- R t-Bu2FSi 12a, b Figure 3. Molecular structure of 10b (left) and simplified ...
The reaction is stoichiometric; one mole of DTBP producing one mole of dehydrodimer and two moles of t-BuOH, when excess methyl oleate is used. The dimer was shown to contain two double bonds, and to be formed by carbon-to-carbon linkages predominantly and equally at the 8, 9, 10 and...
(c) ICRACinhibitory effects of the next five purified fractions obtained from ODS MPLC. Abbreviations: BTP2, 3,5-bis(trifluoromethyl) pyrazole derivative; HEX, hexane; CHCl3, chloroform; EtOAc, ethyl acetate; BuOH, butanol; H2O, water; MeOH, methanol; MPLC, medium-pressure liquid ...
(a) tBuOH, EDC, DMAP, THF, 18 h, RT; (b) NBS, AIBN, CCl4, 4–6 h, 90 °C; (c) 2,3,4,5-tetrafluoro-N-isopropylbenzenesulfonamide, Cs2CO3, ACN, 6–18 h, RT; (d) 4 M HCl/dioxane, 3–16 h, RT; (e) (i) (COCl)2, THF, DMF, 1 h, 0 °C; (ii) H2N-OTHP, ...
ginseng were extracted with aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH, and H2O, successively. The repeated silica gel and ODS column chromatographies for EtOAc and n-BuOH fraction led to isolation of fourteen ginsenosides, ginsenoside F1 (1), ginsenoside F2 ...