Synthesis of Functionalized [3], [4], [5] and [6]Dendralenes through Palladium‐Catalyzed Cross‐Couplings of Substituted Allenoates
作者:Daniel J. Lippincott、Roscoe T. H. Linstadt、Michael R. Maser、Bruce H. Lipshutz
DOI:10.1002/anie.201609636
日期:2017.1.16
A mild method for the synthesis of highly functionalized [3]–[6]dendralenes is reported, representing a general strategy to diversely substituted higher homologues of the dendralenes. The methodology utilizes allenoates bearing various substitution patterns, along with a wide range of boron and alkenyl nucleophiles that couple under palladium catalysis leading to sp‐, sp2‐, and sp3‐substituted arrays
Functionalized α-bromocyclopropylmagnesium bromides: Generation and some reactions
作者:I. G. Bolesov、V. A. Solov’eva、M. S. Baird
DOI:10.1134/s1070428013110043
日期:2013.11
boxylic acids and their esters) undergo partial hydrodebromination at the treatment with isopropyl magnesium bromide (3–6 mol-equiv) in THF and then in methanol at −60°C affording the corresponding monobromides in 64–95% yields. The addition of nonsolvated magnesium bromide to the reaction mixture results in the considerable reduction of the amount of the Grignard reagent (from 6 to 3 mol-equiv). This
Coolade. A Low‐Foaming Surfactant for Organic Synthesis in Water
作者:Nicholas R. Lee、Margery Cortes‐Clerget、Alex B. Wood、Daniel J. Lippincott、Haobo Pang、Farbod A. Moghadam、Fabrice Gallou、Bruce H. Lipshutz
DOI:10.1002/cssc.201900369
日期:2019.7.5
Several types of reduction reactions in organic synthesis are performed under aqueous micellar‐catalysis conditions (in water at ambient temperature), which produce a significant volume of foam owing to the combination of the surfactant and the presence of gas evolution. The newly engineered surfactant “Coolade” minimizes this important technical issue owing to its low‐foaming properties. Coolade is
Synthesis and Application of Chiral Cyclopropane-Based Ligands in Palladium-Catalyzed Allylic Alkylation
作者:Gary A. Molander、Jason P. Burke、Patrick J. Carroll
DOI:10.1021/jo048782s
日期:2004.11.1
A series of chiral, cyclopropane-based phosphorus/sulfur ligands have been synthesized and evaluated in the palladium-catalyzedallylicalkylation of 1,3-diphenylpropenyl acetate with dimethyl malonate. Variation of the ligand substituents at phosphorus, sulfur, and the carbon backbone revealed 24d to have the optimal configuration for this reaction, giving the product in high yield and with good enantioselectivity
Versatile Synthesis of Cyclopropanecarboxylic Acid Derivatives by the Ni(CO)<sub>4</sub>-Induced Reductive Carbonylation Reaction of<i>gem</i>-Dibromocyclopropanes
Reductive carbonylation of gem-dibromocyclopropanes was achieved by treatment with tetracarbonylnickel in the presence of alcohols, amines, thiols, or imidazole in DMF leading to the corresponding cyclopropanecarboxylic acid derivatives, respectively. Use of disulfides as an initial nucleophile resulted in carbonylation with sulfenylation at the geminal position. This method was applied to the intramolecular