70960-90-6Relevant academic research and scientific papers
PALLADIUM-CATALYZED DIASTEREOSELECTIVE SYNTHESES OF (E)-1-TRIMETHYLSILYL-2-ALKENES, (E)-1-TRIMETHYLSILYL-1-ALKEN-3-YNES, (1E,5E)-1-TRIMETHYLSILYL-1,5-ALKADIEN-3-YNES, (1E,3Z)- AND (1E,3E)-1-TRIMETHYLSILYL-1,3-ALKADIENES
Andreini, Bianca Patrizia,Carpita, Adriano,Rossi, Renzo,Scamuzzi, Barbara
, p. 5621 - 5640 (2007/10/02)
On the basis of our observation that (E)-1-bromo-1-alkenes undergo preferentially stereospecific Pd-catalyzed cross-couplings with a variety of organometallics, in the presence of the corresponding (Z)-stereoisomers, efficient and convenient diastereoselective procedures have been developed to prepare nearly stereoisomerically pure (E)-1-trimethylsilyl-2-alkenes (4), (E)-1-trimethylsilyl-1-alken-3-ynes (5), (1E,5E)-1-trimethylsilyl-1,5-alkadien-3-ynes (6), and (1E,3E)-1-trimethylsilyl-1,3-alkadienes (8) from stereoisomeric mixtures of alkenyl bromides.Compounds 5 have been stereoselectively converted into (1E,3Z)-1-trimethylsilyl-1,3-dienes (7) by selective hydrometallations, followed by hydrolysis.Some synthetic applications of compounds 5-8 have been also examined.
HIGHLY DIASTEREOSELECTIVE SYNTHESIS OF (E)-1-TRIMETHYLSILYL-1-EN-3-YNES, (1E,3Z)- and (1E,3E)-1-TRIMETHYLSILYL-1,3-DIENES
Andreini, Bianca Patrizia,Carpita, Adriano,Rossi, Renzo
, p. 2239 - 2242 (2007/10/02)
In the stereospecific palladium-catalysed cross-coupling reaction of 1-alkynylzinc chlorides or (E)-1-alkenyl diisobutylalanes, (E)-2-bromovinyltrimethylsilane reacts preferentially, in the presence of the corresponding (Z)-stereoisomer to afford good yields of (E)-1-trimethylsilyl-1-en-3-ynes (4) or (1E,3E)-1-trimethylsilyl-1,3-dienes (6),respectively, having very high stereoisomeric purities.Compounds 4 are easily converted into (1E,3Z)-1-trimethylsilyl-1,3-dienes (5) by selective hydrometallation reactions, followed by protonolysis.
