Formal<i>anti</i>-Carbopalladation Reactions of Non-Activated Alkynes: Requirements, Mechanistic Insights, and Applications
作者:Martin Pawliczek、Tobias F. Schneider、Christian Maaß、Dietmar Stalke、Daniel B. Werz
DOI:10.1002/anie.201411210
日期:2015.3.23
Formal anti‐carbopalladation reactions of CC triple bonds are uncommon, but highly useful transformations. Alkynes can be designed to give anti‐carbopalladation products. Prerequisite is the exclusion of other reaction pathways to provoke the cis–trans isomerization of the syn‐carbopalladation intermediate. Detailed mechanistic studies of this crucial step by experimental and computational means were
Ruthenium-Catalyzed Cycloisomerizations of Diynols
作者:Barry M. Trost、Michael T. Rudd
DOI:10.1021/ja043097o
日期:2005.4.1
[CpRu(CH(3)CN)(3)]PF(6). The formation of five- and six-memberedrings is possible using this methodology. Secondary diynols react to form single geometrical isomeric dienones and -als. Primary diynols undergo a cycloisomerization as well as a hydrative cyclization process. The utility of primary diynol cycloisomerization is demonstrated in a synthesis of (+)-alpha-kainic acid.
An Unusual Ruthenium-Catalyzed Cycloisomerization of Alkynes and Propargyl Alcohols
作者:Barry M. Trost、Michael T. Rudd
DOI:10.1021/ja012672a
日期:2002.4.1
CpRu(NCCH3)3+PF6- catalyzes the cycloisomerization of diyne-ols to alpha,beta,gamma,delta-unsaturated aldehydes and ketones in good-to-excellent yields. 1-Hydroxy-2,7-diynes and 1-hydroxy-2,8-diynes can be utilized to form highly functionalized five- and six-membered rings, respectively. Tertiary as well as secondary propargyl alcohols are cycloisomerized to a single isomeric product. A wide variety
Cobalt-mediated regio- and stereoselective assembly of dienamides by hydroaminative alkyne coupling of α,ω-diynes
作者:Vincent Gandon、Corinne Aubert、Max Malacria、K. Peter C. Vollhardt
DOI:10.1039/b716841a
日期:——
In the presence of CpCo(C(2)H(4))(2), alpha,omega-diynes undergo hydroaminative coupling with amides to furnish new dienamides with control of regio- and stereochemistry.
(Bpin)2 as the boron reagent in dimethyl sulfoxide at room temperature. Both terminal and internal propargyl alcohols with diverse structures and functional groups underwent the transformation smoothly to produce β-Bpin-substituted (E)-allylic alcohols, of which the synthetic potentials were demonstrated by the downstream conversions of boronate, alkenyl, and hydroxylgroups.