Quiz - Carbon-Carbon Bond Formation - 2 | Carbon-Carbon Bond Formation

Organic Chemistry 3 - Quiz - Carbon-Carbon Bond Formation - 2


Which coupling reaction would be most suitable for forming a carbon-carbon bond between an aryl halide and an alkenylborane?

The Suzuki Reaction is the most suitable for this purpose because it couples aryl halides with organoboron compounds, often using a palladium catalyst under mild conditions. This reaction has high tolerance for various functional groups and is widely used in organic synthesis.


What is the main purpose of using an organocuprate reagent (Gilman reagent) in coupling reactions?

Organocuprate reagents are used in carbon-carbon bond formation for their ability to perform conjugate addition to enone systems (α,β-unsaturated carbonyl compounds), also known as 1,4-addition. These reagents are mild and selective, allowing for the introduction of alkyl groups to the α-position of enones.


In the Heck reaction, what is the role of the palladium catalyst?

In the Heck reaction, the palladium catalyst inserts into the carbon-halide bond of the aryl halide, facilitating the subsequent formation of a carbon-carbon bond with the alkene. This reaction is utilized to form carbon-carbon bonds in the synthesis of complex molecules.


Which carbon-carbon bond-forming reaction involves a copper acetylide and is useful for coupling terminal alkynes?

The Sonogashira Reaction involves the formation of a copper acetylide intermediate and is widely used for coupling terminal alkynes with aryl or vinyl halides. The reaction commonly employs a palladium catalyst and a copper co-catalyst.


What is the nature and reactivity of carbenes in organic synthesis?

Carbenes are neutral reactive intermediates with a divalent carbon atom with only six electrons in its valence shell, making them electrophilic. They can add to electron-rich double bonds, insert into C-H bonds, and participate in cyclopropanation reactions.


The Simmons-Smith Reaction is best described by which of the following?

The Simmons-Smith Reaction involves the formation of cyclopropanes from alkenes using a carbenoid reagent, typically a zinc-copper couple and diiodomethane. This reagent generates an active carbenoid species that adds across double bonds to form cyclopropanes.


What distinguishes the metathesis reaction from other carbon-carbon bond-forming reactions?

Metathesis is characterized by the exchange of alkylidene groups between alkenes, typically catalyzed by metal carbene complexes, such as those of ruthenium or molybdenum. This reaction can produce complex carbon skeletons with high selectivity and efficiency.


What is a notable characteristic of the Suzuki reaction regarding the stereochemistry at the carbon-carbon bond forming site?

In the Suzuki reaction, the stereochemistry at the carbon-carbon bond forming site is retained during the reaction, meaning the relative configuration of substituents remains unchanged.


When synthesizing complex molecules, the selective formation of carbon-carbon bonds in the presence of functional groups is best achieved by which reaction?

The Suzuki Reaction is distinguished by its tolerance for a wide variety of functional groups and ability to selectively form carbon-carbon bonds under mild conditions. This makes it highly valuable in the synthesis of complex and functionalized molecules.


Which aspect of carbenes is manipulated in the Simmons-Smith Reaction for the successful formation of cyclopropanes?

In the Simmons-Smith Reaction, the electrophilic nature of carbenes is utilized to form cyclopropanes. A carbenoid species, which simulates the reactivity of carbenes, is generated and reacts readily with alkenes to produce cyclopropanes.