Mol amount

Amount of substance mole mol Amount of substance which contains as many specified entities as there are atoms of car-bon-12 in exactly 0.012 kg of that nuclide. The elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles. 

An early example of the use of a subcatalytic amoimt of sparteine for the activation of an organolithium nucleophile was reported by Lautens et al. in the carbometallation of a meso-unsaturated oxabicycle 25, with ring opening leading to the substituted cycloheptene derivative 26 (Scheme 4) [4]. Both yield and enantiomeric excess remained virtually unchanged when the ratio n-BuLi sparteine was lowered to 1 0.15. However, when a 3 mol% amount of the ligand 1 was used, a 20% decrease in enantioselectivity was observed. 

When membrane retention of the solute needs to be considered, one can derive the appropriate permeability equations along the lines described in the preceding section Eqs. (7.1)—(7.3) apply (with P designated as the effective permeability, Pe). However, the mass balance would need to include the membrane compartment, in addition to the donor and acceptor compartments. At time t, the sample distributes (mol amounts) between three compartments ... 

Method Average Distribution M range (g/mol) Amount/mg Operating expense... 

All the reactions described so far are carried out using stoichiometric amounts of Co2(CO)8. However, a coordinatively unsaturated 02(00)5 species would be liberated when the rearrangement proceeds, and if this cobalt species could form an alkyne-Co2(CO)6 complex with another molecule of 1-(1-alkynyl) cyclopropanol, the reaction should proceed with only a catalytic amount of 02(00)8 [13, 18]. In practice, when 1-phenylethynylcyclopropanol (11b) is treated with a 10 or 20 mol% amount of 02(00)8, the rearranged product 13b is obtained in 43 and 59 % yield, respectively. Thus, the reaction in fact proceeds with a catalytic amount of 02(00)8 however, the efficiency is low and a complex mixture of by-products is also obtained. As this low efficiency could be ascribed to instability of the unsaturated cobalt species, the catalytic reaction could be made more efficient by the addition of a stabilizing additive. 

The products of the electrochemical perfiuorination of alcohols are perfluorocyclic ethers and, in fair yields, perfluoroalkanoyl fluorides.39 The products of the electrochemical perfiuorination of 3-methylbutan-l-ol (1) (0.2 mol amount of charge 482.4 kC current density 3.5 A dm"2 voltage 5-10 V temperature 5-6 C) are shown. 

During in vivo studies under biologically relevant conditions, the cis-Pt loading of the DNA is much lower than for the above-mentioned in vitro studies. It has been calculated that mortality of HeLa cells occurs at an value of 10 5 (i.e., one bound cis-Pt molecule per 105 nucleotides) (64a). This excludes atomic absorption spectroscopy for identification of the in vivo adducts. Immunochemical techniques, however, have shown to be very promising, and high sensitivity and selectivity levels have been reached. At the moment, only a few studies in which antibodies are raised against cis-Pt-treated DNA (64) or against synthetic cis-Pt adducts with mono- or dinucleotides are available (64a). With the latter method, quantitation of the different platinum-DNA adducts formed under in vivo conditions is possible. At the moment, femtomole (10-15 mol) amounts of the adducts can be detected with competitive enzyme-linked immunosorbent assay (ELISA) techniques. It has been demonstrated in this manner that the GG-Pt adduct is also the predominant adduct under in vivo conditions. 

Studies are ongoing to establish not only the induction but also the repair of the various Pt-DNA adducts, because it is assumed that incorrectly repaired and nonrepaired, persistent, lesions will be responsible for the antitumor effects of the drug. For the study of the Pt-adduct formation and repair in DNA of cells treated with biologically relevant doses, e.g. from patients treated with cisplatin, very sensitive detection methods are required. For this purpose immunochemical techniques have been developed with which, at the moment, femtomol (10 15 mol) amounts of the Pt-adducts in DNA can be detected with anh-Pt-adduct antibodies120,122,123). 

Sample Molar mass (g/mol) Mass of sample (g) Formula units or molecules Amount of molecules (mol) Amount of atoms (mol)... 

Type of polysaccharide Amount of altrose units (mol.-%) Amount of sorbed iodine (m g) Heat of swelling in water (kcal/mole)... 

Step provides the homoallylic alcohol, predominantly as the anti isomer. The high diastereoselectivity is attributed to the generation of pure ( )-2-butenylzinc in the presence of the electrophile. These reactions can proceed in high yield even with only a catalytic (10 mol%) amount of zinc. 

Initial amount of N2O4 0.476 mol Amount of N2O4 that reacts x(mol)... 

Excellent yields in the epoxidation of alkenes, including terminal ones, have also been obtained by Noyori and co-workers by using Na2WO4 2H2O as the catalyst precursor under solvent-free (or in toluene) and halide free conditions (Scheme 3) The efficiency of the reaction is dependent on the use of aminomethylphosphonic acid and trioctylmethyl ammonium hydro-gensulfate as additives in 1 mol% amount, which are the best performing conditions. 

Molar mass of styrene (CgHg) = 8x12 -f- 8x1 = 104 g/mol Molar mass of initiator, (C6HsC0)202 = 242 g/mol Amount of initiator = 0.20 g... 

The first catalytic asymmetric [2+2] cycloaddition reaction was reported in 1989 by the use of the chiral titanium reagent prepared from the tartrate-derived chiral 1,4-diol 1 and TiCl2(0-z-Pr)2 [26]. Treatment of methyl ( )-4-oxo-4-(2-oxo-l,3-oxazolidin-3-yl)-2-butenoate (2a) and l,l-bis(methylthio)ethylene (3a) with a 10 mol % amount of the chiral titanium reagent in a mixed-solvent of toluene and petroleum ether (RE.) at 0 °C afforded the cyclobutane derivative 4a in 96% yield in nearly optically pure form (98% ee) (Scheme 1). In this section we... 

Lewis acids used for acylation of allylsilanes with acid chlorides include titanium and tin tetrachlorides, aluminum, gallium and indium trichlorides and zinc dichloride, and boron trifluoride for reactions with acid anhydrides. Although gallium and indium chlorides have been used successfully in catalytic (ca. 2 mol %) amounts, most frequently aluminum chloride has been used as catalyst, with titanium tetrachloride also commonly employed, both in molar quantities. With these catalysts, acylations can often be carried out at low temperatures, and with short reaction times. 

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