Dess-Martin Periodinane Research Articles

Desymmetrization of Hepta-1,6-dien-4-ol by a Highly Stereo­selective Tandem Prins–Ritter Cyclization: Access to New THP Acetamides

Prins–Ritter cyclization performed from hepta-1,6-dien-4-ol and various aldehydes, promoted by bismuth(II) triflate, afforded N-(tetrahydropyranyl)acetamides in moderate to high yields. Subsequent Wacker-type oxidation using Dess–Martin periodinane (DMP) delivered the corresponding ketones.

Generation of Magnesium Pentafluoropropen-2-olate from Hexafluoroisopropanol and Synthesis of 2,2,4,4,4-Pentafluoro-3,3-dihydroxyketones.

2,2,4,4,4-Pentafluoro-3,3-dihydroxyketones are valuable precursors to difluoroenolates following fragmentation during the release of trifluoroacetate; however, there are few synthetic strategies to prepare this unique class of compound. We addressed this issue and report a mild, two-step synthesis of 2,2,4,4,4-pentafluoro-3,3-dihydroxyketones from aldehydes. Specifically, aldehydes are treated with pentafluoropropen-2-olate, generated from a new fragmentation of hexafluoroisopropanol with a mixed Mg/Li amide, to give pentafluoroalcohols. A subsequent oxidation with Dess-Martin periodinane provides the targets in good isolated yields.

Diethylamine Dess–Martin periodinane: an efficient catalyst–oxidant combination in a sequential, one-pot synthesis of difficult to access 2-amino-3,5-dicarbonitrile-6-sulfanylpyridines at ambient temperature

A problem solving approach towards high yielding synthesis of 2-amino-3,5-dicarbonitrile-6-sulfanylpyridines is described. Simple isolation and avoidance of chromatographic purification are the noteworthy advantages.

Synthesis of 2,2-bis(pyridin-2-yl amino)cyclobutanols and their conversion into 5-(pyridin-2-ylamino)dihydrofuran-2(3H)-ones.

A two-step protocol is presented for the preparation of 5-(pyridin-2-ylamino)dihydrofuran-2(3H)-ones from 2-hydroxycyclobutanone and some 2-aminopyridines via a catalyst-free synthesis of 2,2-bis(pyridin-2-ylamino)cyclobutanols followed by Dess-Martin periodinane mediated ring expansion.

ChemInform Abstract: Hypervalent Iodine as a Terminal Oxidant in Wacker‐Type Oxidation of Terminal Olefins to Methyl Ketones.

AbstractA Markovnikov‐selective oxidation of terminal olefins by a combination of palladium(II) acetate and Dess—Martin periodinane is described.

Catalytic Hypervalent Iodine Promoters Lead to Styrene Dimerization and the Formation of Tri- and Tetrasubstituted Cyclobutanes.

Reported herein is that the use of catalytic quantities of hypervalent iodine reagents (phenyliodine diacetate or Dess-Martin periodinane) allows the rapid and stereoselective formation of cyclobutanes under very mild reaction conditions. The presence of a fluorinated solvent is essential for the success of these reactions which form unsymmetrical tri- and tetrasubstituted cyclobutanes through a heterodimerization process involving two different alkenes.

Catalytic Hypervalent Iodine Promoters Lead to Styrene Dimerization and the Formation of Tri‐ and Tetrasubstituted Cyclobutanes

AbstractReported herein is that the use of catalytic quantities of hypervalent iodine reagents (phenyliodine diacetate or Dess–Martin periodinane) allows the rapid and stereoselective formation of cyclobutanes under very mild reaction conditions. The presence of a fluorinated solvent is essential for the success of these reactions which form unsymmetrical tri‐ and tetrasubstituted cyclobutanes through a heterodimerization process involving two different alkenes.

Hypervalent Iodine as a Terminal Oxidant in Wacker-Type Oxidation of Terminal Olefins to Methyl Ketones.

A mimic of the Wacker process for C═O bond formation in terminal olefins can be initiated by a combination of the Pd(II) and hypervalent iodine reagent, Dess-Martin periodinane to generate methyl ketones. This operationally simple and scalable method offers Markovnikov selectivity, has good functional group compatibility, and is mild and high yielding.

Copper-Catalyzed Intramolecular Oxidative Amination of Unactivated Internal Alkenes.

A copper-catalyzed oxidative amination of unactivated internal alkenes has been developed. The Wacker-type oxidative alkene amination reaction is traditionally catalyzed by a palladium through a mechanism involving aminopalladation and β-hydride elimination. Replacing the precious and scarce palladium with a cheap and abundant copper for this transformation has been challenging because of the difficulty associated with the aminocupration of internal alkenes. The combination of a simple copper salt, without additional ligand, as the catalyst and Dess-Martin periodinane as the oxidant, promotes efficiently the oxidative amination of allylic carbamates and ureas bearing di- and trisubstituted alkenes leading to oxazolidinones and imidazolidinones. Preliminary mechanistic studies suggested a hybrid radical-organometallic mechanism involving an amidyl radical cyclization to form the key C-N bond.

Beyond the Dimer and Trimer: Tetraspiro[2.1.2(5).1.2(9).1.2(13).1(3)] hexadecane-1,3,5,7-tetraone--the Cyclic Tetramer of Carbonylcyclopropane.

Tetraspiro[2.1.2(5).1.2(9).1.2(13).1(3)]hexadecane-1,3,5,7-tetraone 4, a unique tetraketone containing a cyclooctane core and four spiroannelated cyclopropane moieties, represents the previously unknown cyclotetramer of carbonylcyclopropane. For this purpose oxidation of the parent polyspirocyclic hydrocarbon was examined under various oxidative conditions, and the reactivity of oxidants towards methylene groups of the eight-membered cycle, activated by adjacent spirocyclopropane rings, was evaluated and contrasted. Whereas the treatment of tetraspirohexadecane with ozone resulted in monooxidation, its reaction with methyl(trifluoromethyl)dioxirane afforded the product of four-fold oxidation, triketoalcohol 10. Subsequent oxidation of the latter with Dess-Martin periodinane gave the target tetraketone 4.

One-pot preparation of labelled mannan-peptide conjugate, model for immune cell processing.

An efficient method for preparation of fluorescently labelled mannan-peptide glycoconjugates has been developed. After selective Dess-Martin periodinane oxidation of mannan, it was conjugated to the fluorescent label alone and a peptide with the label via reductive amination. Prepared glycoconjugates were characterised by HPSEC, FTIR-ATR and UV-VIS spectroscopy. Finally, the fluorescently labelled mannan and mannan-peptide conjugate were used for microscopic visualization of their accumulation in intracellular organelles of RAW 264.7 cells.

ChemInform Abstract: Alkynyl Trifluoromethyl Selenide Synthesis via Oxidative Trifluoromethylselenolation of Terminal Alkynes.

The synthesis of alkynyl trifluoromethyl selenides by Cu-mediated oxidative trifluoromethylselenolation of terminal alkynes is reported. Treatment of [(bpy)Cu(SeCF3)]2 with various terminal alkynes in the presence of an oxidant, Dess–Martin periodinane, led to the formation of trifluoromethylselenolated acetylenes bearing sensitive moieties such as alkoxy, halogens, trifluoromethyl, and heterocyclic groups.

A Study of the Reactivity of Polyhydroxylated Sterol Derivatives

AbstractA detailed study of regiospecific silylation, oxidation, and reduction of sterols is reported. The different reactivity of 2α and 3α hydroxy groups is demonstrated on a 2α,3α‐dihydroxy‐5α‐pregnane‐6,20‐dione as a model substrate. A regiospecific silylation of the 2α‐alcohol occurred when silyl chloride was used under mild reaction conditions. The selective oxidation of one of the 2α,3α‐diols by dimethyldioxirane or the Dess–Martin periodinane led to a mixture of α‐hydroxyketones with high prevalence of 3,6,20‐trione over 2,6,20‐trione in the ratio 10:1. A regiospecific reduction of a model substrate by lithium tri‐tert‐butoxyaluminium hydride gives the C6 alcohol.

Nghiên cứu quy trình tổng hợp febrifugine hydrochloride

Febrifugine, a quinazoline alkaloid, isolated from Dichroa febrifuga roots, shows powerful antimalarial activity against Plasmodium falciparum. Strong liver toxicity has precluded febrifugine as a potential clinical drug. However, the potent antimalarial activity of febrifugine has stimulated medicinal chemists to pursue compounds derived from febrifugine, which may be valuable leads for novel drugs. Total synthesis and structural modification of febrifugine have been made. Among the reported asymmetric approaches to febrifugine, one of the most straight forward approaches to construct the 2-substituted 3-hydroxy piperidine is the stereoselective reaction of 3-hydroxy-piperidine N-acyliminium ions with the nucleophiles. In this study, we synthesized febrifugine hydrochloride (13) from L-glutamic acid (1) base on the asymmetric BF3.Et2O catalyzed nucleophilic reactions. The precursor 12 was formed by open epoxy ring using triethylamine and then oxidation with Dess-Martin periodinane. Their structures were established by MS and NMR spectroscopies. Keywords: Febrifugine, antimalarial activity.

Synthesis and Growth-Stimulating Activity of 15β-substituted Brassinosteroids

15β-Hydroxybutylcastasterone and its 24-epimer were synthesized from (20S)-15β-(4-benzoyloxybutyl)-20-hydroxymethyl-2α,3α-isopropylidenedioxy-6,6-ethylenedioxy-5α-pregn-16-ene using a sequence of transformations including hydrogenation of the double bond by H2 over Adams’ catalyst, oxidation by Dess–Martin reagent, Julia olefination, Sharpless catalytic dihydroxylation, and hydrolysis of protecting groups. The compounds exhibited activity in growth-stimulating tests that was comparable with those of castasterone and 24-epicastasterone.

The First Stereoselective Synthesis of a Dithiane Derivative of the C18 β-Diketodiene System Proposed for an Active Compound Isolated from Cantharellus cibarius (Chanterelle)

A stereocontrolled synthesis of a thioketal system that is a direct precursor of an active compound isolated from chanterelle was accomplished by using readily available methyl 11-[2-(2-oxoethyl)-1,3-dithian-2-yl]undec-9-ynoate as a key intermediate. The synthesis involves simple and straightforward reactions, such as addition of a lithiated alkyne to an aldehyde, alkyne hydrogenation using nickel boride, alcohol oxidation with Dess–Martin periodinane, and Z-to-E enone isomerization.

Synthetic studies of alkaloids containing pyrrolidine and piperidine structural motifs.

Awarding Institute: Goa University (India) Date awarded: December, 2013 Supervisor: Prof. Santosh G. Tilve, HOD Chemistry, Goa University, Goa (India)

A highly regio- and stereoselective synthesis of α-fluorinated imides via fluorination of chiral enamides.

A highly π-facial selective and regioselective fluorination of chiral enamides is described. The reaction involves an enantioselective fluorination exclusively at the electron-rich enamide olefin with N-F reagents such as Selectfluor and N-fluoro-benzenesulfonimide [NFSI] accompanied by trapping of the β-fluoro-iminium cationic intermediate with water. The resulting N,O-hemiacetal could be oxidized using Dess-Martin periodinane, leading to an asymmetric sequence for syntheses of chiral α-fluoro-imides and optically enriched α-fluoro-ketones.

Total synthesis of 3-epi-(+)-lycoricidine from Garner aldehyde via intramolecular aldol cyclization

A highly efficient total synthesis of 3-epi-(+)-lycoricidine has been described for the first time from easily available (S)-Garner aldehyde with an overall yield of 7% in 20 steps. Stereoselective nucleophilic addition, Sharpless asymmetric dihydroxylation, Dess–Martin periodinane oxidation, intramolecular aldol cyclization, and Luche reduction are the salient features of this approach.

Differential Oxidation Conditions of Substituted Cyclobutanols Derived from Terpenes

The use of different oxidants for homochiral cyclobutanols afforded dissimilar products depending on the agent used. Dess–Martin periodinane allowed us to obtain the homochiral cyclobutanones and sodium hypochlorite produced only one of the two possible regioisomeric γ-butyrolactones.