59376-58-8Relevant articles and documents
Ligand effects on the stereochemistry of Stille couplings, as manifested in reactions of Z-alkenyl halides
Lu, Guo-Ping,Voigtritter, Karl R.,Cai, Chun,Lipshutz, Bruce H.
supporting information; experimental part, p. 8661 - 8663 (2012/09/25)
Unexpected losses in stereochemistry from Stille reactions involving Z-alkenyl halides have been shown to be ligand dependent. A new set of reaction conditions has been developed that, in most cases, leads to highly stereoselective cross-couplings under mild conditions, along with improved yields.
Highly selective synthesis of conjugated dienoic and trienoic esters via alkyne elementometalation - Pd-catalyzed cross-coupling
Wang, Guangwei,Mohan, Swathi,Negishi, Ei-Ichi
, p. 11344 - 11349 (2011/10/30)
All four stereoisomers (7-10) of ethyl undeca-2,4-dienoate were prepared in ≥98% isomeric purity by Pd-catalyzed alkenylation (Negishi coupling) using ethyl (E)- and (Z)-β-bromoacrylates. Although the stereoisomeric purity of the 2Z,4E-isomer (8) prepared by Suzuki coupling using conventional alkoxide and carbonate bases was ≤95%, as reported earlier, the use of CsF or nBu4NF as a promoter base has now been found to give all of 7-10 in ≥98% selectivity. Other widely known methods reveal considerable limitations. Heck alkenylation was satisfactory for the syntheses of the 2E,4E and 2E,4Z isomers of ≥98% purity, but the purity of the 2Z,4E isomer was ≤95%. Mutually complementary Horner-Wadsworth-Emmons and Still-Gennari (SG) olefinations are also of considerably limited scopes. Neither 2E,4Z nor 2Z,4Z isomer is readily prepared in ≥90% selectivity. In addition to (2Z,4E)-dienoic esters, some (2Z,4E,6E)- and (2Z,4E,6Z)-trienoic esters have been prepared in ≥98% selectivity by a newly devised Pd-catalyzed alkenylation-SG olefination tandem process. As models for conjugated higher oligoenoic esters, all eight stereoisomers for ethyl trideca-2,4,6-trienoate (23-30) have been prepared in ≥98% overall selectivity.
Palladium-catalysed Reaction of Vinylic Halides with Allylic Alcohols: A Highly Chemo-, Regio- and Stereo-controlled Synthesis of Conjugated Dienols
Jeffery, Tuyet
, p. 324 - 325 (2007/10/02)
A new, direct, highly chemo-, regio- and stereo-controlled method for the construction of (E,E) and (E,Z) conjugated dienols from vinylic halides and allylic alcohols is described.
Structural Dynamics of Pentadienyl Metal-Compounds Bearing a Terminal Alkyl Substituent: Both 'Stereoselective' and 'Stereodefensive' Synthesis of a Natural Perfume
Bosshardt, Herbert,Schlosser, Manfred
, p. 2393 - 2403 (2007/10/02)
The (2Z,4E)-, (2E,4Z)- and (2E,4E)-isomers of 2,4-decandien-1-ol (5) have been obtained with high and predictable stereochemical homogeneity starting from both (Z)- and (E)-1,4-decadiene.These hydrocarbons were hydroxylated in a reaction sequence consisting of metallation (by means of s-butyllithium or butyllithium/potassium-t-butoxide, giving rise to organometallic intermediates of specific conformations), dimethoxyborylation and oxidation.The different decadienols as well as (2E,4Z)-2,4-undecadien-1-ol were converted into the isovalerates, the ester derived from (2E,4Z)-2,4-decadien-1-ol being a natural flavor component.