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Matthew L. Crawley

Other affiliations: Main Line Health, Williams College
Bio: Matthew L. Crawley is an academic researcher from Stanford University. The author has contributed to research in topics: Allylic rearrangement & Enantioselective synthesis. The author has an hindex of 7, co-authored 13 publications receiving 2394 citations. Previous affiliations of Matthew L. Crawley include Main Line Health & Williams College.

Papers
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Journal ArticleDOI
TL;DR: Alkylations with Phenols, Nitrogen Nucleophiles in AAA Total Synthesis, and Considerations for Enantioselective Allylic Alkylation are presented.
Abstract: A. Primary Alcohols as Nucleophiles 2931 B. Carboxylates as Nucleophiles 2931 C. Alkylations with Phenols 2932 IV. Nitrogen Nucleophiles in AAA Total Synthesis 2935 A. Alkylamines as Nucleophiles 2935 B. Azides as a Nucleophile 2936 C. Sulfonamide Nucleophiles 2937 D. Imide Nucleophiles 2938 E. Heterocyclic Amine Nucleophiles 2940 V. Sulfur Nucleophiles 2941 VI. Summary and Conclusions 2941 VII. Acknowledgment 2941 VIII. References 2942 I. Considerations for Enantioselective Allylic Alkylation

2,230 citations

BookDOI
22 Jun 2012
TL;DR: In this article, the transition metal-catalyzed synthesis of five and six-membered Heterocycles was used to synthesize transition metal catalysts in the pharmaceutical industry.
Abstract: Preface vii Contributors ix About the Authors xi 1 Transition Metal Catalysis in the Pharmaceutical Industry 1 Carl A. Busacca, Daniel R. Fandrick, Jinhua J. Song, and Chris H. Senanayake (Boehringer Ingelheim Pharmaceuticals) 2 Selected Applications of Transition Metal-Catalyzed Carbon Carbon Cross-Coupling Reactions in the Pharmaceutical Industry 25 Hong C. Shen (Roche) 3 Selected Applications of Pd- and Cu-Catalyzed Carbon Heteroatom Cross-Coupling Reactions in the Pharmaceutical Industry 97 Jingjun Yin (Merck) 4 Asymmetric Cross-Coupling Reactions 165 Vince Yeh (Novartis) and William A. Szabo (Consultant in Drug Development) 5 Metathesis Reactions 215 Oliver R. Thiel (Amgen) 6 Transition Metal-Catalyzed Synthesis of Five- and Six-Membered Heterocycles 257 Cheol K. Chung (Merck) and Matthew L. Crawley (Main Line Health) 7 Oxidative Catalysis 277 Lamont Terrell (GlaxoSmithKline) 8 Industrial Asymmetric Hydrogenation 315 Hans-Ulrich Blaser (Solvias) Index 343

124 citations

Journal ArticleDOI
TL;DR: 4-(2'-Naphthoxy)-2- butenolide, readily available with high enantiopurity by a dynamic kinetic asymmetric transformation (DYKAT) of racemic 4-acyloxybutenolides, serves as an excellent chiral building block where the naphth oxygen group strongly directs the stereochemistry of cycloadditions to the double bond.
Abstract: 4-(2‘-Naphthoxy)-2-butenolide, readily available with high enantiopurity by a dynamic kinetic asymmetric transformation (DYKAT) of racemic 4-acyloxybutenolides (available in two steps from furfural), serves as an excellent chiral building block where the naphthoxy group strongly directs the stereochemistry of cycloadditions to the double bond. Notably, the cycloadditions of trimethylenemethanepalladium intermediates which do not exhibit good diastereoselectivity in additions to acceptors that possess many common and important chiral auxiliaries undergo cycloadditions with excellent regio- and stereocontrol. The utility of this process set the stage for an efficient new synthesis of (+)-brefeldin A, a compound of growing pharmacological significance. This synthesis also highlights the Pd-catalyzed DYKAT of crotyl carbonate to create the remote stereocenter. A new two-step method to convert aldehydes to δ-hydroxy-E-α,β-enoates is also outlined.

81 citations

Journal ArticleDOI
TL;DR: Chiral gamma-aryloxybutenolides, readily accessible through dynamic kinetic asymmetric transformation (DYKAT), were utilized as "chiral aldehyde" building blocks for intermolecular cycloadditions and Michael reactions and inspired work that culminated in the total synthesis of (+)-brefeldin A, a natural product with a range of significant biological properties.
Abstract: Chiral gamma-aryloxybutenolides, readily accessible through dynamic kinetic asymmetric transformation (DYKAT) of racemic acyloxybutenolides, were utilized as "chiral aldehyde" building blocks for intermolecular cycloadditions and Michael reactions. Unprecedented selectivity in trimethylenemethane cycloadditions with this building block allowed an efficient synthesis of a novel metabotropic glutamate receptor 1 antagonist in development by the Bayer corporation. These studies further inspired work that culminated in the total synthesis of (+)-brefeldin A, a natural product with a range of significant biological properties. All of the stereochemistry in this target molecule was derived from two palladium-catalyzed asymmetric allylic alkylation reactions. The trans-alkenes were synthesized by a Julia olefination and a ruthenium-catalyzed trans-hydrosilylation-protodesilylation protocol. The route to (+)-brefeldin A lends itself to analogue syntheses and was completed in 18 steps in 6 % overall yield.

59 citations

Journal ArticleDOI
TL;DR: These data are the first to demonstrate the dramatic lowering of serum LDLc levels by a FXR agonist in primates and supports the potential utility of 14cc in treating dyslipidemia in humans beyond just TG lowering.
Abstract: In an effort to develop orally active farnesoid X receptor (FXR) agonists, a series of tetrahydroazepinoindoles with appended solubilizing amine functionalities were synthesized. The crystal structure of the previously disclosed FXR agonist, 1 (FXR-450), aided in the design of compounds with tethered solubilizing functionalities designed to reach the solvent cavity around the hFXR receptor. These compounds were soluble in 0.5% methylcellulose/2% Tween-80 in water (MC/T) for oral administration. In vitro and in vivo optimization led to the identification of 14dd and 14cc, which in a dose-dependent fashion regulated low density lipoprotein cholesterol (LDLc) in low density lipoprotein receptor knockout (LDLR(-/-)) mice. Compound 14cc was dosed in female rhesus monkeys for 4 weeks at 60 mg/kg daily in MC/T vehicle. After 7 days, triglyceride (TG) levels and very low density lipoprotein cholesterol (VLDLc) levels were significantly decreased and LDLc was decreased 63%. These data are the first to demonstrate the dramatic lowering of serum LDLc levels by a FXR agonist in primates and supports the potential utility of 14cc in treating dyslipidemia in humans beyond just TG lowering.

53 citations


Cited by
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Journal ArticleDOI
TL;DR: A review of palladium-catalyzed coupling of CH bonds with organometallic reagents through a PdII/Pd0 catalytic cycle can be found in this paper.
Abstract: Pick your Pd partners: A number of catalytic systems have been developed for palladium-catalyzed CH activation/CC bond formation. Recent studies concerning the palladium(II)-catalyzed coupling of CH bonds with organometallic reagents through a PdII/Pd0 catalytic cycle are discussed (see scheme), and the versatility and practicality of this new mode of catalysis are presented. Unaddressed questions and the potential for development in the field are also addressed. In the past decade, palladium-catalyzed CH activation/CC bond-forming reactions have emerged as promising new catalytic transformations; however, development in this field is still at an early stage compared to the state of the art in cross-coupling reactions using aryl and alkyl halides. This Review begins with a brief introduction of four extensively investigated modes of catalysis for forming CC bonds from CH bonds: PdII/Pd0, PdII/PdIV, Pd0/PdII/PdIV, and Pd0/PdII catalysis. A more detailed discussion is then directed towards the recent development of palladium(II)-catalyzed coupling of CH bonds with organometallic reagents through a PdII/Pd0 catalytic cycle. Despite the progress made to date, improving the versatility and practicality of this new reaction remains a tremendous challenge.

3,533 citations

Journal ArticleDOI
TL;DR: This Review highlights recent applications of controlled microwave heating in modern organic synthesis, and discusses some of the underlying phenomena and issues involved.
Abstract: Although fire is now rarely used in synthetic chemistry, it was not until Robert Bunsen invented the burner in 1855 that the energy from this heat source could be applied to a reaction vessel in a focused manner. The Bunsen burner was later superseded by the isomantle, oil bath, or hot plate as a source for applying heat to a chemical reaction. In the past few years, heating and driving chemical reactions by microwave energy has been an increasingly popular theme in the scientific community. This nonclassical heating technique is slowly moving from a laboratory curiosity to an established technique that is heavily used in both academia and industry. The efficiency of "microwave flash heating" in dramatically reducing reaction times (from days and hours to minutes and seconds) is just one of the many advantages. This Review highlights recent applications of controlled microwave heating in modern organic synthesis, and discusses some of the underlying phenomena and issues involved.

3,044 citations

Journal ArticleDOI
Chao-Jun Li1
TL;DR: This work over the past several years to form carbon-carbon bonds directly from two different C-H bonds under oxidative conditions, cross-dehydrogenative coupling (CDC) is described, which provides an alternative to the separate steps of prefunctionalization and defunctionsalization that have traditionally been part of synthetic design.
Abstract: Synthetic chemists aspire both to develop novel chemical reactions and to improve reaction conditions to maximize resource efficiency, energy efficiency, product selectivity, operational simplicity, and environmental health and safety. Carbon−carbon bond formation is a central part of many chemical syntheses, and innovations in these types of reactions will profoundly improve overall synthetic efficiency. This Account describes our work over the past several years to form carbon−carbon bonds directly from two different C−H bonds under oxidative conditions, cross-dehydrogenative coupling (CDC). We have focused most of our efforts on carbon−carbon bonds formed via the functionalization of sp3 C−H bonds with other C−H bonds. In the presence of simple and cheap catalysts such as copper and iron salts and oxidants such as hydrogen peroxide, dioxygen, tert-butylhydroperoxide, and 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ), we can directly functionalize various sp3 C−H bonds by other C−H bonds without requiring ...

2,308 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