Gas affordability

Mild acidic hydrolysis of amino nitrile 369 gave m-4,9a-/7-rra r-9-7/-9-benzyloxy-4-phenyl-3,4,9,9a-tetrahydro-17/,67/-pyrido[2,l-d[l,4]oxazin-l-one <1996TL4001>. (2A)-2-Cyano-l-[(lR)-2-hydroxy-l-phenylethyl]piperidin-6-one, on standing for 20 days in ethanol saturated with HC1 gas, afforded (4/ ,9aA)-4-phenylperhydropyrido[l,2-4[l,4]oxazine-l,6-dione, which was sometimes accompanied by the unstable (26 )-l-[(l/ )-2-hydroxy-l-phenylethyl]-... 

The most convenient method of preparing thio derivatives of 1,2,4-thiadiazoles is by a type E synthesis. Treating dipotassium cyanodithioiminocarbonate with chlorine gas affords 5-thio-substituted 1,2,4-thiadiazoles. Alternatively, treatment with sulfur followed by chlorine gas affords 3,5-bisthio-substituted 1,2,4-thiadiazoles <1996CHEC-II(4)307>. 

The annexed tables, by Dr. Dyfe, contain, in addition to the quantities of gas afforded by the coals, much valuable information upon, the relative illuminating values of the gases, which he arrived at by the chlorine teat. When chlorine ia added to coal-gas, it forms with the olefiant gas and the vapors of tar oil—with those constituents, therefore, upon which the illuminat-... 

This table exhibits the quantity of gas afforded from a ton of each of the coals the specific gravity of the gas the amount of condensible matter by chlorine the durability of the gas when burned by a single jet with a five-inch flame the comparative value of the gas for affording light, as shown by the chlorine test, by the durability, and by these taken together, which,... 

Yamamoto and coworkers have developed a practical Diels-Alder catalyst for aldehyde dienophiles. Treatment of a monoacylated tartaric acid with borane released ca. 2.2 equiv of H2 gas, affording a complex that has been assigned structure 7. Circrunstantial evidence for structure 7 was found in the comparable enan-tioselectivity of a catalyst in which the free carboxyl group was esterified (see below). The chiral (acyloxy)borane (CAB) complex is effective in catalyzing a number of aldehyde-based Diels-Alder reactions (Scheme 9) [56]. Reactions with... 

Radical-mediated deiodination, methanolysis of the acetate and subsequent oxidation of the resulting alcohol furnished the ketone 43 in 87% total yield. Transformation of 43 into the corresponding cyanohydrin acetate under ordinary conditions resulted in the formation of a diastereomeric mixture 44 and 45. However, only the kinetically favored cyanohydrin acetate 44 was obtained when treated with hydrogen cyanide and pyridine. Treatment of the nitrile 44 with HCl gas afforded the amide 46, which was subjected to alkaline hydrolysis followed by esterification of the resulting carboxyhc acid with diazomethane to furnish 5 in 11% overall yield from 27. 

So far, three sesquiterpenes are known which, when treated with hydrochloric acid gas, afford Isevo-rotatory cadinene hydrochloride namely —... 

Other workers describe how addition of carbon disulfide to hepta-6-amino-6-deoxy-p-cyclodextrin in the presence of ammonia gas affords a mixture of partially substimted dithiocarbamate derivatives. When bound to a silver electrode, they are capable of discriminating between the three positional isomers of the nitrobenzoate ion and nitrophenol (as detected by cyclic voltammetry) an effect that is attributed to the different orientations of the nitro group with respect to the silver surface after inclusion in the cyclodexttin cavity (1835). 

An enzyme extract of tryptophan side chain oxidase from Pseudomonas oxidizes iV-acetyl tryptophanamide to iV-acetyl A -tryptophanamide. Enantioselective [Rh-DIPAMP] -catalyzed reduction (DIPAMP = (IR, 2R)-bis[(2-methoxyphenyl)phenylphosphino]eth-ane) with tritium gas afforded the (5)-enantiomer in an optical purity of 94 % and nearly theoretical specific activity... 

To prepare 3-CD polymers, the solution of P-CD in DMF was treated with HMDI in DMF and the resulting precipitate was filtered off the obtained activated polymer is the support 43. The solution of 43 in acetonitrile was reacted with ethylenediamine in acetonitrile to give 44, which upon treatment with GA afforded the activated polymer which is the support 45. ... 

Only few chiral auxiliary-based approaches are available that provide general access to optically active [2 + 2]-photocycloaddition products. One notable example is the approach using unsaturated bicyclic lactams reported by Meyers (Scheme 18.39) [147]. Irradiation of 234 in the presence of ethylene gas afforded cycloadduct 235 in 94 6 dr and 93 % yield. This cyclobutane intermediate could be readily converted into grandisol (236) after removal of the chiral auxiliary. 

Continuous production of (/ )-mandelic acid in an enzyme membrane reactor was reported by Kula et al. [122]. a-Hydroxy esters can be obtained from these acids in the usual ways. They are also accessible directly from the cyanohydrins by a modified Pinner synthesis conversion in diethyl ether, in the presence of 2 equivalents of the alcohol and 2 equivalents of HCl gas, affords the iinidate salt (Scheme 10). By dissolving this salt in water, it is rapidly and quantitatively converted to the corresponding ester [46,98]. If R-cyanohydrins of p-substituted pivaldehydes, like -methoxy- or P-chloropivaldehyde, are hydrolized with concentrated HCl, (jR)-pantolactone is obtained in good yield and high enantiomeric excess [103] (Scheme 11). 

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