598-18-5Relevant academic research and scientific papers
Method for preparing halogen propanol and epoxypropane
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Paragraph 0098; 0099; 0110; 0111; 0129; 0130, (2017/05/19)
The invention provides a method for preparing halogen propanol. The method comprises the following steps (1) halogen alcoholization: adding halogen hydride, H2O2, propylene and an HTS molecular sieve into a reaction device, and carrying out halogen alcoholization reaction to obtain the halogen propanol. The invention also provides a method for preparing epoxypropane with a halogenohydrin method. The method comprises the following steps: (1) halogen alcoholization: adding halogen hydride, H2O2, propylene and an HTS molecular sieve into the reaction device, and carrying out the halogen alcoholization reaction to obtain halogen propanol; (2) saponification: carrying out saponification reaction on halogen propanol and a hydroxide of alkali metal in step (1), and separating to obtain the epoxypropane and alkali halide metal salt; optionally (3) electroosmosis: carrying out bipolar membrane electroosmosis on the alkali halide metal salt obtained in step (2) to obtain the hydroxide of alkali metal and the halogen hydride. According to the methods, the halogen propanol or the epoxypropane can be prepared at extremely high selectivity and yield, and the discharging of waste water and waste residues can be drastically lowered.
Asymmetric alkyl-alkyl cross-couplings of unactivated secondary alkyl electrophiles: Stereoconvergent suzuki reactions of racemic acylated halohydrins
Owston, Nathan A.,Fu, Gregory C.
supporting information; experimental part, p. 11908 - 11909 (2010/11/04)
A method for asymmetric alkyl-alkyl Suzuki reactions of unactivated secondary alkyl electrophiles, specifically, cross-couplings of racemic acylated halohydrins with alkylborane reagents, has been developed. A range of protected bromohydrins, as well as a protected chlorohydrin and a homologated bromohydrin, are coupled in good ee by a catalyst derived from commercially available components.
O-phenylenediamine as a new catalyst in the highly regioselective conversion of epoxides to halohydrins with elemental halogens - A reinvestigation
Soroka, Miroslaw,Goldeman, Waldemar
, p. 169 - 174 (2007/10/03)
In contrast to a previous report, o-phenylenediamine is not a catalyst in the ring opening reaction of epoxides by means of bromine or iodine. The o-phenylenediamine is just a reactant which reacts with iodine to give phenazine-2,3-diamine and hydrogen iodide, or with bromine to give a mixture of brominated and polymerized products as well as hydrogen bromide. The hydrogen halogenides are in fact the real epoxide ring opening reactants. Springer-Verlag 2006.
Reinvestigation of the conversion of epoxides into halohydrins with elemental halogen catalysed by thiourea
Soroka, Miros?aw,Goldeman, Waldemar
, p. 4233 - 4235 (2007/10/03)
In contrast to a previous literature report, thiourea is not a catalyst in the ring opening reaction of epoxides by means of bromine or iodine. Instead, thiourea reacts with the halogen to give a complex mixture of products, among them hydrogen halogenides, which are in fact the real epoxide ring opening reactants. The presence of water is crucial in this reaction.
Comments on a Conversion of Epoxides to Halohydrins with Elemental Halogen Catalyzed by Phenylhydrazine: Tandem Electrophilic Halogenation of Aromatic Compounds and Epoxide Ring Opening to Halohydrins
Soroka, Miroslaw,Goldeman, Waldemar,Malysa, Piotr,Stochaj, Monika
, p. 2341 - 2344 (2007/10/03)
The halogenation of aromatic compounds by bromine or chlorine in the presence of an epoxide gives the corresponding halogenated aromatics and 2-halohydrins, both with good yields.
Highly regio- and stereoselective synthesis of β-halohydrins from epoxides catalyzed with ceric ammonium nitrate
Iranpoor,Kazemi,Salehi
, p. 1247 - 1258 (2007/10/03)
Ce(IV) as ceric ammonium nitrate can effectively catalyze ring opening of epoxides with halides under very mild conditions and easy procedure to give the corresponding β-chloro- and β-bromohydrins in excellent yields. The reactions occur with both substituted and unsubstituted quaternary ammonium halides and with high regio- and stereoselectivity. The reaction of optically active styrene oxide with chloride ion was found to be highly stereospecific and afforded the corresponding β-halohydrin in 96% ee.
Free Radical Macrocyclizations from Steroid-Derived Precursors
Scott, Daniel M.,McPhail, Andrew T.,Porter, Ned A.
, p. 1178 - 1186 (2007/10/02)
Stereoselective free radical addition reactions were studied using steroid-derived templates in an attempt to control product dispersity.Templates were prepared from bifunctional steroids appropriately substituted with initiating and terminating functionality.Free radical initiation in the presence of a polymerizable olefin resulted in the formation of macrocycles that had incorporated monomer.The yield of macrocycle formed was as 51percent for templates derived from lithocholic acid whereas templates derived from androstanolone failed to give significant amounts of macrocycles.The effects of variation of initiating and terminating functionality, steroid, and olefin on macrocycle size and yield were examined.
Highly Regioselective and Stereospecific Functionalization of 1,2-Proanediol with Trimethyl(X)silanes Employing the 1,3,2λ5-Dioxaphospholane Methodology
Mathieu-Pelta, Isabel,Evans, Slayton A.
, p. 3409 - 3413 (2007/10/02)
The regioselective ring opening of (S)-4-methyl-2,2,2-triphenyl-1,3,2λ5-dioxaphospholanes (2) was initiated with several trimethylsilyl reagents (Me3SiX: X = PhS, I, Br; Cl, CN, and N3) to afford the regioisomeric (silyloxy)phosphonium salts.A stereospecific extrusion of triphenylphosphine oxide from these oxyphosphonium salts gave predominatly the thermodynamically less stable C-2-X-substituted derivatives with nearly complete inversion of stereochemistry at the C-2 stereogenic center (i.e., X = PhS).
SULFUR INHIBITORS OF PHOSPHOLIPASE A-Z
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, (2008/06/13)
Phospholipase A2 inhibitors having the formula wherein R" is a C2-C20 alkyl group, R1" is a C1-C4 alkyl group, y is an integer from 2 to 10, and J- is a pharmaceutically acceptable anion, are described
