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Leo A. Paquette

Other affiliations: Heidelberg University
Bio: Leo A. Paquette is an academic researcher from Ohio State University. The author has contributed to research in topics: Ring (chemistry) & Total synthesis. The author has an hindex of 36, co-authored 484 publications receiving 6021 citations. Previous affiliations of Leo A. Paquette include Heidelberg University.


Papers
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Book ChapterDOI
01 Jan 1987
TL;DR: In this paper, a range of different strategies to provide access to the tricyclopentanoid ring system of hirsutene have been described, including annulation procedures for their construction.
Abstract: Hirsutene (1124) is the simplest member of a group of fungal metabolites possessing the linearly fused cis,anti,cis-tricyclo[6.3.0.02,6]undecane carbon skeleton [503]. As a result of the antibiotic and antitumor properties shown by some of these triquinanes, synthetic chemists have strived to devise new annulation procedures for their construction. Several new syntheses of hirsutene itself have recently been reported where a wide range of different strategies to provide access to the tricyclopentanoid ring system are described.

2 citations

Journal ArticleDOI
TL;DR: In this paper, a general procedure for trapping the products of Knoevenagel condensation involving 1,3-diketones and aliphatic aldehydes is described.
Abstract: A general procedure is described for trapping the products of Knoevenagel condensation involving 1,3-diketones and aliphatic aldehydes. Simple stirring of a three-component mixture consisting of each reactant and thiophenol in dichloromethane containing silica gel leads to products in which the 2-alkylidene 1,3-dione has been intercepted to give a (most often) crystalline Michael adduct. The yields are usually quite acceptable, especially if the β-dicarbonyl compound is cyclic. Oxidation of these adducts with sodium periodate regenerates the conjugated enedione, which reacts rapidly with air to give a cyclic peroxide unless protected from the atmosphere. When a monoprotected succinaldehyde is utilized as starting material, hydrolysis of the resultant adduct in aqueous acid results in intramolecular aldolization to give a spirocyclic cyclopentanol

1 citations

Journal ArticleDOI
TL;DR: In this paper, a general approach to the synthesis of enantiomerically pure spirocyclic α,β-butenolides is presented where the fundamental framework is rapidly elaborated by acid- or bromonium ion-induced rearrangement of the carbinol derived by addition of 2-lithio-4,5-dihydrofuran to cyclobutanone.
Abstract: A general approach to the synthesis of enantiomerically pure spirocyclic α,β-butenolides is presented where the fundamental framework is rapidly elaborated by acid- or bromonium ion-induced rearrangement of the carbinol derived by addition of 2-lithio-4,5-dihydrofuran to cyclobutanone. Subsequent resolution of the resulting ketones by either sulfoximine or mandelate acetal technology has been applied effectively. The availability of these building blocks makes possible in turn the acquisition of the enantiomers of dihydrofurans typified by 17, 35, and 38 and lactones such as 25 and 31, as well as the targeted title compounds. Complementary reductions of the early intermediates provide the added advantage that the α- and β-stereoisomeric carbinol series can be obtained on demand. These capabilities have been coordinated to allow the crafting of any member of the series in relatively few steps.

1 citations


Cited by
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Journal ArticleDOI
TL;DR: This review covers the literature published in 2014 for marine natural products, with 1116 citations referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms.

4,649 citations

Journal ArticleDOI
TL;DR: This Review provides an overview of C-H bond functionalization strategies for the rapid synthesis of biologically active compounds such as natural products and pharmaceutical targets.
Abstract: The direct functionalization of C-H bonds in organic compounds has recently emerged as a powerful and ideal method for the formation of carbon-carbon and carbon-heteroatom bonds. This Review provides an overview of C-H bond functionalization strategies for the rapid synthesis of biologically active compounds such as natural products and pharmaceutical targets.

2,391 citations

Journal ArticleDOI
TL;DR: In this Review, highlights of a number of selected syntheses are discussed, demonstrating the enormous power of these processes in the art of total synthesis and underscore their future potential in chemical synthesis.
Abstract: In studying the evolution of organic chemistry and grasping its essence, one comes quickly to the conclusion that no other type of reaction plays as large a role in shaping this domain of science than carbon-carbon bond-forming reactions. The Grignard, Diels-Alder, and Wittig reactions are but three prominent examples of such processes, and are among those which have undeniably exercised decisive roles in the last century in the emergence of chemical synthesis as we know it today. In the last quarter of the 20th century, a new family of carbon-carbon bond-forming reactions based on transition-metal catalysts evolved as powerful tools in synthesis. Among them, the palladium-catalyzed cross-coupling reactions are the most prominent. In this Review, highlights of a number of selected syntheses are discussed. The examples chosen demonstrate the enormous power of these processes in the art of total synthesis and underscore their future potential in chemical synthesis.

2,268 citations

Journal ArticleDOI
Chao-Jun Li1
TL;DR: Reaction of R,â-Unsaturated Carbonyl Compounds 3127: Reaction of R-UnSaturated Carbonies 3127 7.1.6.
Abstract: 4.2.8. Reductive Coupling 3109 5. Reaction of Aromatic Compounds 3110 5.1. Electrophilic Substitutions 3110 5.2. Radical Substitution 3111 5.3. Oxidative Coupling 3111 5.4. Photochemical Reactions 3111 6. Reaction of Carbonyl Compounds 3111 6.1. Nucleophilic Additions 3111 6.1.1. Allylation 3111 6.1.2. Propargylation 3120 6.1.3. Benzylation 3121 6.1.4. Arylation/Vinylation 3121 6.1.5. Alkynylation 3121 6.1.6. Alkylation 3121 6.1.7. Reformatsky-Type Reaction 3122 6.1.8. Direct Aldol Reaction 3122 6.1.9. Mukaiyama Aldol Reaction 3124 6.1.10. Hydrogen Cyanide Addition 3125 6.2. Pinacol Coupling 3126 6.3. Wittig Reactions 3126 7. Reaction of R,â-Unsaturated Carbonyl Compounds 3127

2,031 citations

Journal ArticleDOI
TL;DR: The power of cascade reactions in total synthesis is illustrated in the construction of complex molecules and underscore their future potential in chemical synthesis.
Abstract: The design and implementation of cascade reactions is a challenging facet of organic chemistry, yet one that can impart striking novelty, elegance, and efficiency to synthetic strategies. The application of cascade reactions to natural products synthesis represents a particularly demanding task, but the results can be both stunning and instructive. This Review highlights selected examples of cascade reactions in total synthesis, with particular emphasis on recent applications therein. The examples discussed herein illustrate the power of these processes in the construction of complex molecules and underscore their future potential in chemical synthesis.

1,762 citations