Post Polyketide Synthase Carbon–Carbon Bond Formation in Type-II PKS-Derived Natural Products fromStreptomyces venezuelae

2018 ◽  
Vol 83 (4) ◽  
pp. 1876-1890 ◽  
Author(s):  
Andrew W. Robertson ◽  
Jeanna M. MacLeod ◽  
Logan W. MacIntyre ◽  
Stephanie. M. Forget ◽  
Steven R. Hall ◽  
...  
Keyword(s):  
Natural Products ◽  
Polyketide Synthase ◽  
Bond Formation ◽  
Type Ii ◽  
Carbon Bond ◽  
Carbon Carbon Bond ◽  
Type Ii Pks

Dealkenylative Thiylation of C(sp3)–C(sp2) Bonds

2019 ◽  
Author(s):  
Andrew Smaligo ◽  
Ohyun Kwon
Keyword(s):  
Natural Products ◽  
Bond Formation ◽  
Carbon Bond ◽  
Carbon Carbon Bond ◽  
Synthetic Intermediates ◽  
Anhydrous Solvent ◽  
Synthetic Transformations

Carbon–carbon bond fragmentations are useful methods for the functionalization of molecules. The value of such cleavage events is maximized when paired with a subsequent bond formation. Herein we report a protocol for the cleavage of a C(sp<sup>3</sup>)–C(sp<sup>2</sup>) bond, followed by the formation of a new C(sp<sup>3</sup>)–S bond. This reaction is performed in non-anhydrous solvent and open to the air, employs common starting materials, and can be used to rapidly diversify natural products. We have also subjected the thiylated products to various synthetic transformations, demonstrating their utility as synthetic intermediates.

Dealkenylative Thiylation of C(sp3)–C(sp2) Bonds

2019 ◽  
Author(s):  
Andrew Smaligo ◽  
Ohyun Kwon
Keyword(s):  
Natural Products ◽  
Bond Formation ◽  
Carbon Bond ◽  
Carbon Carbon Bond ◽  
Synthetic Intermediates ◽  
Anhydrous Solvent ◽  
Synthetic Transformations

Carbon–carbon bond fragmentations are useful methods for the functionalization of molecules. The value of such cleavage events is maximized when paired with a subsequent bond formation. Herein we report a protocol for the cleavage of a C(sp<sup>3</sup>)–C(sp<sup>2</sup>) bond, followed by the formation of a new C(sp<sup>3</sup>)–S bond. This reaction is performed in non-anhydrous solvent and open to the air, employs common starting materials, and can be used to rapidly diversify natural products. We have also subjected the thiylated products to various synthetic transformations, demonstrating their utility as synthetic intermediates.

Carbon Dioxide-Mediated C(sp2)–H Arylation of Primary and Secondary Benzylamines

2018 ◽  
Author(s):  
Mohit Kapoor ◽  
Pratibha Chand-Thakuri ◽  
Michael Young
Keyword(s):  
Carbon Dioxide ◽  
Transition Metal ◽  
Bond Activation ◽  
Bond Formation ◽  
Carbon Bond ◽  
Chelate Effect ◽  
Free Amine ◽  
Carbon Carbon Bond ◽  
New Strategy ◽  
Metal Catalyzed

Carbon-carbon bond formation by transition metal-catalyzed C–H activation has become an important strategy to fabricate new bonds in a rapid fashion. Despite the pharmacological importance of <i>ortho</i>-arylbenzylamines, however, effective <i>ortho</i>-C–C bond formation from C–H bond activation of free primary and secondary benzylamines using Pd<sup>II</sup> remains an outstanding challenge. Presented herein is a new strategy for constructing <i>ortho</i>-arylated primary and secondary benzylamines mediated by carbon dioxide (CO<sub>2</sub>). The use of CO<sub>2</sub> is critical to allowing this transformation to proceed under milder conditions than previously reported, and that are necessary to furnish free amine products that can be directly used or elaborated without the need for deprotection. In cases where diarylation is possible, a chelate effect is demonstrated to facilitate selective monoarylation.

Modern Organic Synthesis in the Laboratory

2008 ◽  
Author(s):  
Jie Jack Li ◽  
Chris Limberakis ◽  
Derek A. Pflum
Keyword(s):  
Organic Chemistry ◽  
Graduate Students ◽  
Organic Synthesis ◽  
Functional Group ◽  
Bond Formation ◽  
Reaction Conditions ◽  
Carbon Bond ◽  
Oxidation Reduction ◽  
Carbon Carbon Bond ◽  
Daunting Task

Searching for reaction in organic synthesis has been made much easier in the current age of computer databases. However, the dilemma now is which procedure one selects among the ocean of choices. Especially for novices in the laboratory, it becomes a daunting task to decide what reaction conditions to experiment with first in order to have the best chance of success. This collection intends to serve as an "older and wiser lab-mate" one could have by compiling many of the most commonly used experimental procedures in organic synthesis. With chapters that cover such topics as functional group manipulations, oxidation, reduction, and carbon-carbon bond formation, Modern Organic Synthesis in the Laboratory will be useful for both graduate students and professors in organic chemistry and medicinal chemists in the pharmaceutical and agrochemical industries.

scholarly journals Transition Metal-Catalyzed α-Position Carbon–Carbon Bond Formations of Carbonyl Derivatives

Catalysts ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 861 ◽  
Author(s):  
Ha-Eun Lee ◽  
Dopil Kim ◽  
Ahrom You ◽  
Myung Hwan Park ◽  
Min Kim ◽  
...  
Keyword(s):  
Transition Metal ◽  
Carbonyl Compounds ◽  
Bond Formation ◽  
Chiral Ligand ◽  
Catalytic Systems ◽  
Carbon Bond ◽  
Carbonyl Derivatives ◽  
Carbon Carbon Bond ◽  
Transition Metal Catalyzed ◽  
Metal Catalyzed

α-Functionalization of carbonyl compounds in organic synthesis has traditionally been accomplished via classical enolate chemistry. As α-functionalized carbonyl moieties are ubiquitous in biologically and pharmaceutically valuable molecules, catalytic α-alkylations have been extensively studied, yielding a plethora of practical and efficient methodologies. Moreover, stereoselective carbon–carbon bond formation at the α-position of achiral carbonyl compounds has been achieved by using various transition metal–chiral ligand complexes. This review describes recent advances—in the last 20 years and especially focusing on the last 10 years—in transition metal-catalyzed α-alkylations of carbonyl compounds, such as aldehydes, ketones, imines, esters, and amides and in efficient carbon–carbon bond formations. Active catalytic species and ligand design are discussed, and mechanistic insights are presented. In addition, recently developed photo-redox catalytic systems for α-alkylations are described as a versatile synthetic tool for the synthesis of chiral carbonyl-bearing molecules.

Sign in / Sign up

Export Citation Format

Share Document