Showing papers in "Tetrahedron in 1982"

TL;DR: In this article, a general, versatile method for alkylation and arylation of haloheterocyclic compounds is reported, in the presence of a catalytic quantity of [NiCl 2 (dppp)], where dppp stands for Ph 2 P(CH 2 ) 3 PPh 2, bromothiophenes, halopyridines, haloquinoline, and haloisoquinolines reacted with alkyl and Grignard reagents at room temperature or at ether refluxing temperature to give the cross-

TL;DR: Suicide substrates are defined as a class of irreversible inactivators of specific target enzymes where the target enzyme participates in its own destruction by catalytic unmasking of a latent functional group at some stage in the catalytic cycle of the enzyme.

TL;DR: An extension of the nomenclature for classifying ring closures to include intramolecular reactions of enolate anions is described, and the rules governing such cyclizations are enumerated as discussed by the authors.

TL;DR: Several derivatives of 3-ketocoumarins were prepared and are shown to have many of the photophysical criteria required for efficient triplet sensitizers as mentioned in this paper, which is an important criterion for efficient sensitization of thin films of polymers.

TL;DR: The chemistry and biology of the ant venom alkaloids from the genera Solenopsis and Monomorium are briefly reviewed in this paper, where the usual 2,6-dialkylpiperidines found in four as yet unstudied species of solenopsis are described.

TL;DR: The defensive secreation of chrosomelid larvae and adults has been analyzed in this article, where Salicyaldehyde and some already known methylcyclopentanoid monoterpenes have been identified in the larvae.

TL;DR: Cadlina luteomarginata was found to consume at least ten sponges although Axinella sp. and Myxilla incrustans are most frequently eaten.

TL;DR: In this article, the lawesson reagent (LR) was applied to cyclohexanone and cyclopentanone at 80° with formation of new spiro - 1,3,5,2 - trithiaphosphorines 1 and 2, respectively.

TL;DR: In this article, the authors showed that triphenylene can be reversibly oxidized to a mono-cation HET+, a dication HET2+, a trication Het3+, and a tetraction HET4+.

TL;DR: Several open chain ligands (polypodands) 3 and 4 have been synthesized introducing short oligoethylene glycol units (-CH 2 CH 2 O) m CH 3, (m = 1,2) on lipophilic matrices represented by cyclic tetra- 1 and octa- 2 oligomers obtained from the base catalyzed reaction of p-butylphenol or p-octyl phenol as mentioned in this paper.

TL;DR: In this paper, mild and efficient synthesis of β-substituted "capped"-porphyrins and meso-tetraphenylporphrins from the corresponding porphyrins is described.

TL;DR: In this paper, 3-Bromo- or 3-iodo-cinnoline derivatives are condensed with terminal alkynes in the presence of Pd and Cu compounds as catalysts to give the 3-alkynyl-derivatives.

TL;DR: In this paper, a short synthesis of the title compound, 16, from d -ribonolactone is described, and two alternative approaches differing in the timing of the CC double bond creation are used to prepare some chiral derivatives of 16.

TL;DR: In this paper, the results of the nickel peroxide and chromic acid oxidation were compared to those of the NiC peroxide, chromic acids, and nickel oxide hydroxide regenerated at a nickel hydroxyde electrode.

TL;DR: In this paper, a large syn-selectivity was observed on reaction with cis-alkenes and this selectivity increased with the size of the substituents, and suggested a preferential direction of the alkene towards a rhodium-carbene complex.

TL;DR: In this article, the effect of temperature, concentration, external magnetic fields and paramagnetic quenchers on the lifetime of triplet-derived Biradicals has been examined and attributed to conformational memory in the singlet Biradical which reflects its short lifetime.

TL;DR: The structures of three potent molluscicides balanitin-1, -2 and -3 which were isolated from the East African tree Balanites aegyptiaca have been determined to be 1, 2 and 3, respectively as mentioned in this paper.

TL;DR: In this article, the structure of HC-toxin (C21H32N4O6) was determined as cyclo [(2-amino-9,10-epoxy-8-oxodecanoyl)-alanyl-alanylprolyl] based upon spectral evidence.

TL;DR: In this paper, a degraded terpenoid was found in Cadlina luteomarginata, collected in Howe Sound and Barkley Sound, British Columbia, Canada, and was shown to contain sesquitepenoids and a degradation of the carbon skeleton.