α- and β-Functionalized Ketones from 1,3-Dienes and Aldehydes: Control of Regio- and Enantioselectivity in Hydroacylation of 1,3-Dienes

Parsutkar, Mahesh M.; RajanBabu, T. V.

doi:10.1021/jacs.1c06245

Cited by 49 publications

(28 citation statements)

References 76 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…45 After an extensive search for ligands and optimized reaction conditions, we have identified the best conditions for regio-and enantioselective hydroacylations of 2-and 4monosubstituted, and 2,4-disubstituted 1,3-dienes. 4 The results of these studies are summarized in Figure 11 (2-mono-and 2,4disubstituted 1,3-dienes giving predominantly 1,2-adduct) and Figure 12 (4-substituted 1,3-dienes giving 4,1-or 4,3-adducts depending on the nature of the aldehyde). Particularly noteworthy are the use of two feedstock dienes, isoprene and myrcene, in these reactions.…”

Section: ■ Regiodivergent Hydroalkenylation Of 16-enynes and An Uncom...mentioning

confidence: 99%

“…Similar experiments have been carried out with enantioselective hydroacylation of isoprene (entries 6−10). 4 Isolated neutral Co(I) complex (29) derived from i-PrDUPHOS ligand (entry 7) or an in situ prepared "Zn-reduced" Co(I)-Br derived from the corresponding CoBr 2 complex (entry 10) itself does not affect the hydroacylation reaction. Addition of NaBARF turns these into excellent catalysts (entries 6 and 9).…”

Section: ■ Regio-and Enantioselective Hydroboration Of 13-dienesmentioning

confidence: 99%

“…In 2014, Dong reported the first examples of a racemic version of the cobalt-catalyzed hydroacylation of 1,3-dienes and showed that regioselectivity (1,2- versus 1,4-addition) could be controlled by the steric and electronic properties of the chelating phosphines . After an extensive search for ligands and optimized reaction conditions, we have identified the best conditions for regio- and enantioselective hydroacylations of 2- and 4-monosubstituted, and 2,4-disubstituted 1,3-dienes . The results of these studies are summarized in Figure (2-mono- and 2,4-disubstituted 1,3-dienes giving predominantly 1,2-adduct) and Figure (4-substituted 1,3-dienes giving 4,1- or 4,3-adducts depending on the nature of the aldehyde).…”

Section: Regio- and Enantioselective Hydroacylation Of 13-dienesmentioning

confidence: 99%

“…2 These complexes have since been found to be equally good catalysts for synthesis of cyclobutenes via enantioselective [2 + 2]-cycloadditions of alkynes and alkenyl derivatives. 3 Further, these complexes are also applicable for other regio-and enantioselective hydrofunctionalization reactions such as hydroacylations 4 and hydroborations. 5 Most gratifyingly, we find that the cationic cobalt(I) catalysts with appropriate ligands enable tandem reactions of enynes such as cycloaddition−hydrovinylation 6 and cycloisomerization−hydroalkenylation.…”

Section: ■ Introductionmentioning

confidence: 99%

“…2021, 143, 12825−12835. 4 Cationic Co(I) complexes carrying electron-rich bisphospholanes are excellent catalysts for hydroacylation reactions. This work discusses how the regio-and enantioselectivity in the hydroacylation of 1,3-dienes can be controlled by ligands and choice of aldehydes.…”

mentioning

confidence: 99%

See 4 more Smart Citations

A New Paradigm in Enantioselective Cobalt Catalysis: Cationic Cobalt(I) Catalysts for Heterodimerization, Cycloaddition, and Hydrofunctionalization Reactions of Olefins

et al. 2021

Self Cite

View full text Add to dashboard Cite

Conspectus One of the major challenges facing organic synthesis in the 21st century is the utilization of abundantly available feedstock chemicals for fine chemical synthesis. Regio- and enantioselective union of easily accessible 1,3-dienes and other feedstocks like ethylene, alkyl acrylates, and aldehydes can provide valuable building blocks adorned with latent functionalities for further synthetic elaboration. Through an approach that relies on mechanistic insights and systematic examination of ligand and counterion effects, we developed an efficient cobalt-based catalytic system [(P∼P)CoX2/Me3Al] (P∼P = bisphosphine) to effect the first enantioselective heterodimerization of several types of 1,3-dienes with ethylene. In addition to simple cyclic and acyclic dienes, siloxy-1,3-dienes participate in this reaction, giving highly functionalized, nearly enantiopure silyl enolates, which can be used for subsequent C–C and C–X bond-forming reactions. As our understanding of the mechanism of this reaction improved, our attention was drawn to more challenging partners like alkyl acrylates (one of the largest volume feedstocks) as the olefin partners instead of ethylene. Prompted by the intrinsic limitations of using aluminum alkyls as the activators for this reaction, we explored the fundamental chemistry of the lesser known (P∼P)Co(I)X species and discovered that in the presence of halide sequestering agents, such as sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (NaBARF) or (C6F5)3B, certain chiral bisphosphine complexes are superb catalysts for regio- and enantioselective heterodimerization of 1,3-dienes and alkyl acrylates. We have since found that these cationic Co(I) catalysts, most conveniently prepared in situ by reduction of the corresponding cobalt(II) halide complexes by zinc in the presence of NaBARF, promote enantioselective [2 + 2]-cycloaddition between alkynes and an astonishing variety of alkenyl derivatives to give highly functionalized cyclobutenes. In reactions between 1,3-enynes and ethylene, the [2 + 2]-cycloaddition between the alkyne and ethylene is followed by a 1,4-addition of ethylene in a tandem fashion to give nearly enantiopure cyclobutanes with an all-carbon quaternary center, giving a set of molecules that maps well into many medicinally relevant compounds. In another application, we find that the cationic Co(I)-catalysts promote highly selective hydroacylation and 1,2-hydroboration of prochiral 1,3-dienes. Further, we find that a cationic Co(I)-catalyst promotes cycloisomerization followed by hydroalkenylation of 1,6-enynes to produce highly functionalized carbo- and heterocyclic compounds. Surprisingly the regioselectivity of the alkene addition depends on whether it is a simple alkene or an acrylate, and the acrylate addition produces an uncommon Z-adduct. This Account will provide a summary of the enabling basic discoveries and the attendant developments that led to the unique cationic Co(I)-complexes as catalysts for disparate C–C and C–B bond-forming reactions. It...

show abstract

Section: ■ Regiodivergent Hydroalkenylation Of 16-enynes and An Uncom...mentioning

confidence: 99%

Section: ■ Regio-and Enantioselective Hydroboration Of 13-dienesmentioning

confidence: 99%

Section: Regio- and Enantioselective Hydroacylation Of 13-dienesmentioning

confidence: 99%

Section: ■ Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

A New Paradigm in Enantioselective Cobalt Catalysis: Cationic Cobalt(I) Catalysts for Heterodimerization, Cycloaddition, and Hydrofunctionalization Reactions of Olefins

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

Rhodium(I) Catalyzed Hydroacylation Reactions of Alkenyl Compounds

Zhao,

Lu,

Wang

et al. 2024

Adv Synth Catal

View full text Add to dashboard Cite

Transition‐metal‐catalyzed hydroacylation of unsaturated substrates with aldehydes involving the formyl C(sp2)–H bond activation provides an expedient and efficient access to the carbonyl compounds such as ketones and esters, which are a class of important scaffolds in natural products and in drug development. Recently, extensive attention has been paid to the hydroacylation reactions of the components containing an alkenyl moiety that can trigger a regioselective transformation in the presence of a transition metal catalyst. In this review, we summarize the constructive endeavors in rhodium(I)‐catalyzed (formal) hydroacylation reactions from 2018, and the plausible pathway is also dissected to offer some insights into the reaction mechanism.

show abstract

Chemodivergent, Regio‐ and Enantioselective Cycloaddition Reactions between 1,3‐Dienes and Alkynes

Singh

RajanBabu

2023

Angewandte Chemie

Self Cite

View full text Add to dashboard Cite

Alkynes and 1,3-dienes are among the most readily available precursors for organic synthesis. We report two distinctly different, catalyst-dependent, modes of regio-and enantioselective cycloaddition reactions between these classes of compounds providing rapid access to highly functionalized 1,4-cyclohexadienes or cyclobutenes from the same precursors. Complexes of an earth abundant metal, cobalt, with several commercially available chiral bisphosphine ligands with narrow bite angles catalyze [4+2]-cycloadditions between a 1,3diene and an alkyne giving a cyclohexa-1,4-diene in excellent chemo-, regio-and enantioselectivities. In sharp contrast, complex of a finely tuned phosphinooxazoline ligand promotes unique [2+2]-cycloaddition between the alkyne and the terminal double bond of the diene giving a highly functionalized cyclobutene in excellent regio-and enantioselectivities.

show abstract

α- and β-Functionalized Ketones from 1,3-Dienes and Aldehydes: Control of Regio- and Enantioselectivity in Hydroacylation of 1,3-Dienes

Cited by 49 publications

References 76 publications

A New Paradigm in Enantioselective Cobalt Catalysis: Cationic Cobalt(I) Catalysts for Heterodimerization, Cycloaddition, and Hydrofunctionalization Reactions of Olefins

A New Paradigm in Enantioselective Cobalt Catalysis: Cationic Cobalt(I) Catalysts for Heterodimerization, Cycloaddition, and Hydrofunctionalization Reactions of Olefins

Rhodium(I) Catalyzed Hydroacylation Reactions of Alkenyl Compounds

Chemodivergent, Regio‐ and Enantioselective Cycloaddition Reactions between 1,3‐Dienes and Alkynes

Contact Info

Product

Resources

About