Showing papers in "Tetrahedron in 1980"
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TL;DR: In this article, a method for the rapid calculation of atomic charges in σ-bonded and nonconjugated π-systems is presented, where only the connectivities of the atoms are considered.
3,640 citations
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TL;DR: In this paper, a new coupling constant-torsion angle relation for the three-bond 1H-1H spin-spin coupling constant is formulated, which includes a correction for the electronegativity of substituents.
1,909 citations
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391 citations
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TL;DR: In this paper, stereo and regiochemical aspects of three reaction types: the SN2' reaction (bimolecular nucleophilic substitution with allylic rearrangement); displacement reactions effected by organometallic reagents; the conversion of allylic alcohols into halides.
326 citations
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324 citations
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TL;DR: Some of the more recent innovations and techniques which have been developed in the past 10-15 years around these features of carboxyl group chemistry are discussed in this article, with a review.
279 citations
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243 citations
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223 citations
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TL;DR: The Bischler-Napieralski dihydroisoquinoline synthesis from N-arylethyl-amides was proven to occur via the imidoyl chlorides and the corresponding nitrilium salt.
171 citations
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TL;DR: In this article, a synthese stereospecifique du p-tolylsulfinyl acetate de t-butyle is described, which permet de realiser, par une condensation du type aldol, des syntheses asymetriques de β-hydroxyacides avec des rendements chimiques de l'ordre de 80% and des taux d'induction generalementeleves (80a90%).
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TL;DR: Kinetic study of the formation and displacement steps has enabled the selection of substituents on the original pyrylium to optimise conditions for both steps for the selective conversion of primary amino groups into many other functionalities under mild conditions in high yields.
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TL;DR: In this article, the 13 C NMR spectra of twenty one iridoid glucosides and fourteen acyl IRD-glucosides of various cyclopentane oxidation states were analyzed and their carbon shifts assigned.
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TL;DR: In this paper, it was found that alkenylhydroquinone ethers can be demethylated with argentic oxide or ceric ammonium nitrate in the presence of 2,4,6-pyridinetricarboxylic acid as a catalyst and afforded ubiquinone-2, menaquinone-1 and their analogs in yields of 53 to 89%.
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TL;DR: The use of the DBMB protecting group in oligoribonucleotide synthesis is described for the first time in this paper, where the first phosphorylation step (leading to phosphodiester intermediates) is carried out by treatment with o -chlorophenyl phosphorodi-(1,2,4-triazolide) (13a ; Ar = 2-C1C 6 H 4 ) and then with water and triethylamine.
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TL;DR: In this paper, the stereochemistry of the formation and breaking of cyclic cyclic phosphorus esters has been investigated and compared with analogous reactions in acyclic phosphoric esters, and it is suggested that nucleophilic substitutions at phosphorus are inherently stereospecific.
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TL;DR: In this paper, β-unsaturated γ-dicarbonyl compounds, easily obtained by reaction of pyridinium chlorochromate with alkylfurans, are interesting starting materials for the rapid synthesis of 3-oxo-cyclopentenes.
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TL;DR: In this paper, a stereoselective synthesis of highly optically pure enantiomers of δ-multistriatin (1 S,2 S,4 S,5 R )-2,4-dimethyl-5-ethyl-6, 8-dioxabicyclo[3.2] was accomplished starting from tartaric acid enantiomer.
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TL;DR: In this paper, the isolation of tetrahydrofurofuran lignans from the roots of A. absinthium and six closely related species is reported, all stereoisomers of 1- [(3,4-methylenedioxy-5-methoxy) phenyl]-4-(3, 4,5-trimethoxyphenyl)-tetrahydron-1H,3H-furo[3-4-c]furan, was found.
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TL;DR: The unsymmetrical N,N,N-trimethyl tris-indolobenzene 3 has been synthesized by several routes, including cyclotrimerization of the O-acetate of indoxyl.
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TL;DR: In this paper, Verschiedene Reaktandgases (CH 4, i -C 4 H 10, NO, N 2 O, Amine,Ather, (CH 3 ) 4 Si) wurden auf ihre Brauchbarkeit bei der bestimmung der Lage von Doppelbindungen durch chemische Ionisations-Massenspektrometrie untersucht.
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TL;DR: In this article, a mechanism involving the elimination of copper hydride to form a hetaryne intermediate was suggested, which yielded 2,2'-biindolyl after hydrolysis.