Application of an organozinc reagent derived from (S)-pyroglutamic acid: a formal synthesis of epibatidine

Karstens, Willem F. J.; Moolenaar, Marinus J.; Rutjes, Floris P. J. T.; Grabowska, Urszula; Speckamp, W. N.; Hiemstra, Henk

doi:10.1016/s0040-4039(99)01808-0

Cited by 28 publications

(16 citation statements)

References 47 publications

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“…This prompted us to explore the use of catalytic amounts of copper, most specifically CuBrؒDMS, which has recently been reported to catalyse the reaction between β-amino zinc reagents and both propargyl and allenyl halides. 8, 9 In addition, we were concerned that the electrophiles that we proposed to use, 8-10, might be susceptible to copper-catalysed isomerisation in the presence of halide ion, which in turn would lead to mixtures of products provided the usual S N 2Ј pathway was followed in the substitution. The use of catalytic amounts of copper might be expected to minimise this problem.…”

Section: Resultsmentioning

confidence: 99%

A new route to hydrophobic amino acids using copper-promoted reactions of serine-derived organozinc reagents

Deboves

Grabowska²,

Rizzo³

et al. 2000

J. Chem. Soc., Perkin Trans. 1

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Section: Resultsmentioning

confidence: 99%

A new route to hydrophobic amino acids using copper-promoted reactions of serine-derived organozinc reagents

Deboves

Grabowska²,

Rizzo³

et al. 2000

J. Chem. Soc., Perkin Trans. 1

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“…Lübke et al synthesized a norleucine derivative starting from ( S )- N -Boc-3-iodo- l -alanine methyl ester 174 , which was reacted with 3-fluorobut-3-enyl tosylate 175 in the presence of activated zinc , affording the targeted methyl 2-((Boc)amino)-5-fluorohex-5-enoate 176 . The tosylate 175 was accessible starting from but-3-en-1-ol 177 by conducting a reaction sequence consisting of concomitant fluorination and bromination of the double bond in the presence of NBS and triethylamine trihydrofluoride as well as benzoyl protection of the primary alcohol to generate the 4-bromo-3-fluorobutyl benzoate 178 .…”

Section: Fluorinated Alkyl α-Amino Acidsmentioning

confidence: 99%

Approaches to Obtaining Fluorinated α-Amino Acids

et al. 2019

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Fluorine does not belong to the pool of chemical elements that nature uses to build organic matter. However, chemists have exploited the unique properties of fluorine and produced countless fluoro-organic compounds without which our everyday lives would be unimaginable. The incorporation of fluorine into amino acids established a completely new class of amino acids and their properties, and those of the biopolymers constructed from them are extremely interesting. Increasing interest in this class of amino acids caused the demand for robust and stereoselective synthetic protocols that enable straightforward access to these building blocks. Herein, we present a comprehensive account of the literature in this field going back to 1995. We place special emphasis on a particular fluorination strategy. The four main sections describe fluorinated versions of alkyl, cyclic, aromatic amino acids, and also nickel-complexes to access them. We progress by one carbon unit increments. Special cases of amino acids for which there is no natural counterpart are described at the end of each section. Synthetic access to each of the amino acids is summarized in form of a table at the end of this article with the aim to make the information easily accessible to the reader.

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“…The reaction tolerates a variety of functional groups such as ester, trifluoromethyl, and nitrile on the aryl iodide (entries 2-6, 10-12, and 14-17) and alkoxy and alkyl on the arylzinc reagent (entries [5][6][7][8][9][10][11][12][13][14][15][16][17]. The reaction also tolerates halides such as chloride and bromide, and ortho-substituents on both aryl iodides (entries 7, 8, 13, and 18) and arylzinc reagents (entries 6-14 and 18).…”

Section: Syn Thesismentioning

confidence: 99%

“…Surprisingly, despite clear evidence of the ability of organozinc reagents to transmetalate to copper halides, as demonstrated both in the stoichiometric syntheses of organocopper(I) complexes 13 and catalytic reactions such as conjugate, 14 allylic, 2a and 1,2-additions, 15 very little is known on the application of copper as a catalyst for the Negishi coupling. 16 In 2004, Ready and Malosh demonstrated that copper could catalyze the reaction of alkylzinc reagents with α-chloro ketones by an S N 2 process (Scheme 1, a). 17 Recently, we also reported that copper(I) iodide could catalyze the cross-couplings of alkyl-, aryl-, and alkynylzinc reagents with heteroaryl iodides under ligand-free conditions (Scheme 1, b).…”

mentioning

confidence: 99%