Showing papers in "Tetrahedron Letters in 1980"

TL;DR: Carbonyl compounds are readily acetalized by alkoxysilanes in the presence of trimethylsilyl trifluoromethanesulfonate catalyst.

TL;DR: The structure of manoalide (1), a sesterterpenoid antibiotic isolated from a marine sponge, has been determined by spectral analysis and chemical transformations in this article.

TL;DR: Organocuprates have been found to be highly stereoselective reagents for the addition of carbanionic nucleophiles to α-asymmetric aldehydes bearing β-oxygen substituents as discussed by the authors.

TL;DR: In this article, a palladium-catalyzed reaction of vinyl bromide with dialkyl phosphite is described, which is stereoselectively prepared by palladium catalyzed reaction.

TL;DR: In this article, various allylic esters of acetoacetic acid undergo rearrangement to give γ, δ-unsaturated methyl ketones in high yields with elimination of carbon dioxide under mild conditions in the presence of catalytic amounts of Pd(OAc) 2 and PPh 3.

TL;DR: In this paper, β-(trimethylsilyl)ethoxymethyl chloride with alcohols afford the corresponding ethers in high yield, using n-Bu4NF in THF or HMPA.

TL;DR: In this paper, a polymer supported method for synthesizing deoxypolyn nucleotides was described, and two non-anucleotides were synthesized in a four-hour time.

TL;DR: Alkylations of chiral amide enolates derived from (l)-prolinol have been shown to yield versatile hydroxy-amides in high diastereomeric purity as mentioned in this paper.

TL;DR: In this paper, three new toxins were isolated from the Red Sea sponge Latrunculia magnifica and a full structure determination of these toxins, by spectroscopic methods, was aided by an X-ray diffraction analysis of a crystalline derivative of latrunculin-A.

TL;DR: Osmium tetroxide catalyzed hydroxylation of sterically hindered olefins proceeds efficiently with trimethylamine Noxide as oxidizing agent in the presence of pyridine as discussed by the authors.

TL;DR: In this article, a new synthesis of the carbapenem ring system, as found in thienamycin and related natural products, has been developed, which involves a highly efficient carbene insertion reaction which produces the bicyclic ring system by forming the N3 bond.

TL;DR: Stereoselective glycosidation and disaccharide formation of uronic acids were performed with silver perchlorate in acetonitrile as discussed by the authors, where the course of the reaction was controlled by intermediate nitrilium acetonitile conjugates, which were generated in situ.

TL;DR: Optically active norbornyl and 1-phenylethyl alcohols and bromides were obtained, respectively, from either norbornene and styrene with trichlorosilane catalyzed by a chiral ferrocenylphosphine-palladium complex followed by treatment with potassium fluoride.

TL;DR: Enolstannanes serve as nucleophiles towards allylic acetates under the influence of palladium(O) catalyst as discussed by the authors, and can be used as catalysts.

TL;DR: Aldehydes are easily converted to 1-bromoolefins or terminal acetylenes by the use of Wittig reaction of bromomethylenetriphenylphosphorane which is prepared from brommethyltriphenymethylphosphonium bromide with potassium tert-butoxide as discussed by the authors.

TL;DR: In this paper, a new convenient route to silyl ethers and esters from alcohols and carboxylic acids using allylsilanes in the presence of an acid catalyst in acetonitrile was developed.

TL;DR: In this paper, the construction of membered rings using alkylthiolates and LDA as nucleophiles is described. But the MIRC reaction is defined only for three, five, six and seven rings.

TL;DR: Both ( E )- and ( Z )-zirconium enolates have been shown to undergo selective kinetic aldol condensation to give mainly erythro -β-hydroxy ketones, esters and amides as mentioned in this paper.

TL;DR: The protected guanosine and uridine derivatives (3a, 3b and 4) react with 1-(mesitylene-2-sulphonyl)-3-nitro-1,2,4-triazole to give 5a, 5b and 7, respectively: 9 is converted into 10 in the same way.

TL;DR: In this paper, the ortho-lithiation of 2, 3, and 4-halopyridines was achieved with lithium diisopropylamide (−78°, tetrahydrofuran) to achieve good yield.

TL;DR: In this article, terminal acetylenes were converted to acetylenecarboxylates in high yields under atmospheric pressure of carbon monoxide at room temperature using a catalytic amount of PdCl 2 and a stoichiometric amount of CuCl 2.

TL;DR: From the root barks of Lycium chinense, a spermine alkaloid, kukoamine A, showing hypotensive activity has been isolated and the structure has been determined as that represented by formula I on the basis of chemical and physical evidence as mentioned in this paper.

TL;DR: Thioanisole derivatives were found to be oxygenated by a reconstituted system of purified cytochrome P-450 to give sulfoxides suggesting the oxygenation to proceed via one electron transfer from sulfides to the active species of the enzyme.

TL;DR: In this article, an efficient and operationally simple synthesis of (±)-thienamycin is described, where the synthesis is based on a simple (1 − )-poly(n) decomposition.

TL;DR: Erythro -3-hydroxy-2-alkylpropionates were prepared in high stereoselectivity and in high isolated yield by zinc borohydride reduction of the corresponding β-keto esters as discussed by the authors.

TL;DR: AlCl 3 has been found to be an efficient reagent for promoting thioacetal and ketalization of carbonyl compounds as mentioned in this paper, and has been shown to be a suitable reagent to promote carbonylation.

TL;DR: In the presence of a catalytic amount of trimethylsilyl trifluoromethanesulfonate, allyltrimethylsilane reacts with acetals to give the corresponding homoallyl ethers in high yields as discussed by the authors.

TL;DR: In this paper, the synthesis and biological characteristics of an SRS-like leukotriene were described, and the synthesis was described in terms of SRS and biological properties.

TL;DR: The reaction of allyl bromides with allyl tin reagents, catalyzed by palladium or zinc chloride gives cross-coupled products without allylic transpostion in the allyl halide partner but with predominate allylic rearrangement from the tin partner as discussed by the authors.

TL;DR: In this paper, allyl-allyl couplings between allylstannanes and allyl acetates catalyzed by palladium(O) were shown to be possible in the presence of a distannane and a palladium catalyst.