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Me groups adjacent to an olefinic double bond were metalated by KOCMe3 and BuLi without cis-trans isomerization. Thus, (E)-MeCH:-CHMe was metalated to give (E)-MeCH:CHCH2K (I) which reacted with ethylene oxide to give 41% (E)-MeCH:CH(CH2)3OH. If I was allo ...
Cis-trans isomerization of proline-like oxazolidines and thiazolidines, denoted pseudo-prolines, is investigated spectrophotometrically with a chymotrypsin coupled assay and by H-1 NMR. A series of peptides carrying substituents of varying stereochemistry ...
Different micellar systems are characterized. Hydroformylation reactions are carried out in the most appropriate ones and are compared with hydroformylations in a non-micellar system. Reaction rates and selectivities for aldehydes are higher than the micel ...
The reactions of the cluster complexes [Pt-3(mu -Co)(3)L-3], where L = PPh3 1a, PPh(2)Bz 1b and PCy3 1c, with activated mono-olefins have been studied under preparative and equilibrium conditions. At low temperature the olefins react quantitatively giving ...
The synthesis of a benzo-15-crown-5 functionalized α-olefin (4′-(undec-10-enylcarboxylate)benzo-15-crown-5, 5) and its terpolymerization with carbon monoxide and various α-olefins are described. A decline of the glass transition temperatures (Tg) of the co ...
A review, with 6 refs., of the prepn. of olefins from phosphonium ylides and carbonyl compds. and from phosphonium ylides, carbonyl compds., org. Li compds., and reactive halogen compds., such as MeCOCH2Cl and EtI. [on SciFinder (R)] ...
Olefins Plants show an intrinsic cost of the energy demand which derives from Process and Plant design. Few innovative changes have been implemented in the past decades. Such changes were mainly directed to increasing the throughput of the plant and its fl ...
A review of kinetic control in the diastereogenic formation of C-C bonds, Diels-Alder reactions, [2 + 2] cyclodimerization of olefins, syn preference in the formation of cyclopropanes from olefins and monosubstituted carbenes, reactions of organometallics ...
Whereas triphenylphosphonioethanide manifests unsatisfactory cis-selectivities (84.0-95.5%), tris(o,o'-difluorophenyl)- and tri-o-tolylphosphonioethanide react with aliph. or arom. aldehydes and, resp., 2-alkenals or 2-alkynals to afford the olefins with c ...
