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单词 stereoselective
释义 stereoselective, a. Chem.|ˌstɛriːəʊ-, ˌstɪəriːəʊsɪˈlɛktɪv|
[f. stereo- + selective a.]
Of a reaction: producing a particular stereoisomeric form of the product preferentially, irrespective of the configuration of the reactant; = stereospecific a. 1 a.
Orig. (quot. 1957) = stereospecific a. 2.
1957Jrnl. Amer. Chem. Soc. LXXIX. 1595/2 Comparable trans eliminations in open-chain systems are stereoselective.1959Ibid. LXXXI. 110/1 A stereospecific process is one in which the configuration of the product is related to that of the reactant... A stereoselective process is one in which there is no relationship between the configuration of the reactant and that of product but one in which there is a definite driving force for forming one of the possible stereoisomeric products.1962E. L. Eliel Stereochem. Carbon Compounds xv. 436 All stereospecific processes are stereoselective, but not all stereoselective processes are stereospecific. For example, the low-temperature free-radical addition of hydrogen bromide to the 2-bromo-2-butenes..is both stereospecific and stereo⁓selective in that the cis olefin gives meso-2,3-dibromobutane whereas the trans olefin gives the dl-dibromide. At higher temperature the reaction is still stereoselective (formation of 75% dl isomer to 25% meso isomer) but no longer stereospecific; both olefins now give the same product mixture.1968[see stereospecific a. 2].1979Canad. Jrnl. Chem. LVII. 646/1 Our synthesis [of sucrose] was predicated upon the stereoselective methoxybromination of the diene 8.
Hence ˌstereoseˈlectively adv.; ˌstereoseˈlection, ˌstereoselecˈtivity, the property or fact of being stereoselective.
1956Jrnl. Amer. Chem. Soc. LXXVIII. 1171/1 The decreased stereoselectivity of ketonization..in the 2-methyl-3-phenylindanone system as compared with the 1-phenyl-2-benzoylcyclohexane situation.1957Ibid. LXXIX. 1594/2 The fact that eliminations from I and II..occur stereoselectively rules out the possibility of an intermediate carbanion of any but very short half-life.1968S. I. Miller in V. Gold Adv. in Physical Org. Chem. VI. 186 We shall then describe a number of causes of stereoselection associated with bonding, steric, thermodynamic [etc.] factors.1974Gill & Willis Pericyclic Reactions vi. 191 Likewise the trans-alkene is formed in the other processes with fairly high stereoselectivity.1979Tetrahedron Lett. 4867 (heading) Stereoselection in the AlCl3-catalysed ene additions of chloral to 1,2-dialkyl ethylenes.1979Canad. Jrnl. Chem. LVII. 646/1 A new synthesis of sucrose in which all of the steps involved proceeded with complete stereoselectivity.1980Chem. in Brit. XVI. 518/1 He was able to put one of the carbon-carbon bonds in place stereoselectively creating two of the six contiguous chiral centres on the left hand side of the molecule.
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