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K. Barry Sharpless was the first to develop a general, reliable enantioselective alkene dihydroxylation, referred to as the Sharpless asymmetric dihydroxylation (SAD). Low levels of OsO 4 are combined with a stoichiometric ferricyanide oxidant in the presence of chiral nitrogenous ligands to create an asymmetric environment around the oxidant.
Enantioselective synthesis, also called asymmetric synthesis, [1] is a form of chemical synthesis. It is defined by IUPAC as "a chemical reaction (or reaction sequence) in which one or more new elements of chirality are formed in a substrate molecule and which produces the stereoisomeric ( enantiomeric or diastereomeric ) products in unequal ...
Sharpless asymmetric dihydroxylation; Sharpless epoxidation [34] Sharpless oxyamination or aminohydroxylation; Shenck ene reaction; Shi epoxidation; Shiina esterification; Shiina macrolactonization or Shiina lactonization; Sigmatropic reaction; Simmons–Smith reaction; Simonini reaction; Simonis chromone cyclization; Simons process; Skraup ...
The Sharpless asymmetric dihydroxylation [7] was developed by K. Barry Sharpless to use catalytic amounts of OsO 4 along with the stoichiometric oxidant K 3 [Fe(CN) 6]. [1] [2] [8] The reaction is performed in the presence of a chiral auxiliary. The selection of dihydroquinidine (DHQD) or dihydroquinine (DHQ) as a chiral auxiliary dictates the ...
The Sharpless oxyamination (often known as Sharpless aminohydroxylation) is the chemical reaction that converts an alkene to a vicinal amino alcohol. The reaction is related to the Sharpless dihydroxylation , which converts alkenes to vicinal diols. [ 1 ]
The two letters AD, stand for asymmetric dihydroxylation. The mix is available in two variations, "AD-mix α" and "AD-mix β" following ingredient lists published by Barry Sharpless. [1] The mixes contain: Potassium osmate K 2 OsO 2 (OH) 4 as the source of Osmium tetroxide; Potassium ferricyanide K 3 Fe(CN) 6, which is the re-oxidant in the ...
In 1992, K.B. Sharpless showed that the asymmetric dihydroxylation conditions developed in his group could be harnessed to give either (R)- or (S)- α-hydroxy ketones from the corresponding silyl enol ethers depending on which Chinchona alkaloid-derived chiral ligands were employed. [22]
The term "click chemistry" was coined by Sharpless around the year 2000, and was first fully described by Sharpless, Hartmuth Kolb, and M.G. Finn at The Scripps Research Institute in 2001. [ 11 ] [ 2 ] This involves a set of highly selective, exothermic reactions which occur under mild conditions; the most successful example is the azide alkyne ...