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A new dimethylsulfoxide activation method employing 1,1-dichlorocycloheptatriene has been developed for a mild Swern-type oxidation of a variety of alcohols. The carbonyl products can be obtained in good to excellent yields from this operationally simple and efficient method. This work is the first report of dimethylsulfoxide activation by a simple chlorinated hydrocarbon reagent, which has the unique ability of equilibrating to its reactive aromatic cationic form.

The enantioselective synthesis of oxylipin-3 has been carried out. The synthetic strategy was started from commercially available n-decanal. The chiral source was based on Sharpless asymmetric dihydroxylation and CBS reduction.

Rather than giving the corresponding aldehyde or carboxylic acid, Jones oxidation of 5-substituted-2-furylethanols gives rise to high yields of the corresponding dihydro-2-(2-oxoethyl)furan-3(2H)-ones, following Achmatowicz-type oxidative ring opening and subsequent reclosure by a 5-exo Michael addition of the pendant hydroxy group to the enedione function. Other oxidation methods such as a Swern reaction give lower yields of the same products while magnesium perphthalate tends to yield the intermediate enediones, and IBX tends to yield the furyl aldehydes.

A facile method for the solid-phase synthesis of pyrrolo[2,1-c][1,4]benzodiazepine dimers has been developed. p-Nitrophenyl carbonate Wang resin attached to 2-amino-5-methoxy-methyl benzoate has been utilized as the resin-bound starting material and these reactions are monitored by FT-IR spectroscopy of resin beads.

A stereodivergent synthesis of N-alkylated 1-deoxygalactonojirimycin and 1-deoxymannojirimycin derivatives has been achieved from a protected 1-deoxynojirimycin intermediate having two free OH groups tactically positioned at C-2 and C-4. The inversion of configuration of the secondary alcohols was performed by way of a Swern oxidation followed by a highly diastereoselective reduction using NaBH 4 or L-Selectride.

An efficient synthesis of cis-2,6-di-(2-quinolylpiperidine) has been developed. The key steps involve Wittig reaction of N-Cbz-protected cis-piperidine-2,6-dicarboxaldehyde (3) with 2-(triphenylphosphinyl- methyl)quinoline bromide (4) and sequential removal of the N-Cbz group and double bond reduction. This synthetic procedure provides an efficient preparation for this useful norlobelane analogue.

The synthesis of the enantiopure C 1 –C 11 fragment of bafilomycin A 1 has been achieved with a 4% overall yield over 18 steps from ( R )-(+)-citronellol. Key steps involve Sharpless asymmetric epoxidation, Miyashita reaction of a γ,δ-epoxymethacrylate with trimethylaluminum in the presence of water, bis-OTMS selective Swern oxidations, Corey–Fuchs alkyne formation, Negishi's carbometalation, and stereoselective formation of the C 2 –C 3 trisubstituted bond of the conjugated diene by a Wittig-type olefination of the α,β-unsaturated C 3 –C 11 aldehyde with the ylide derived from the readily available phosphonium salt [Cl − , Ph 3 P + CH(OMe)COOMe].

Herein we report our results towards the total synthesis of (−)-dolabriferol, describing the synthesis of fragments C1–C9 and C10–C21. This convergent asymmetric approach relies on the use of a common Weinreb amide precursor for the preparation of both fragments, an efficient anti-aldol reaction followed by Zn(BH4)2 reduction to give a 1,3-syn diol, a selective oxidation of a triol under Swern conditions with concomitant lactol formation, and a diastereoselective epoxidation of an allylic alcohol with m-CPBA followed by an efficient epoxide opening with Me2CuCNLi2.

A novel approach to the tricyclic core of the Stemona alkaloids stemofoline and didehydrostemofoline has been discovered that features an intramolecular (3+2) dipolar cycloaddition of an unactivated carbon–carbon double bond with an azomethine ylide; the azomethine ylide was generated by an unprecedented reaction that occurred during a Swern oxidation of an α-(N-cyanomethyl)-β-hydroxy ester. In separate experiments, the efficacy of introducing the requisite oxygen functionality at C(8) and the 1-butenyl side chain at C(3) was established.

The first total synthesis of Botryolide B is described from easily accessible starting materials. The synthetic strategy involves Jacobsen resolution, Sharpless epoxidation, Swern oxidation, Yamaguchi reaction, and ring closing metathesis (RCM).

Treatment by a base, then an acid, of the ester 3, which was prepared by starting from gallic acid 7a, afforded the chromone 6c, whose Swern oxidation, followed by condensation of the resulting aldehyde 6a with the trienyl lithium derivative 13b and methyl iodide, furnished products isomeric with, but not strictly identical to, an authentic sample of O-benzyl stigmatellin 1c.

Primary TMS or TES ethers, in the presence of secondary TMS or TES ethers, are selectively oxidized to the corresponding aldehydes under Swern conditions. A short synthesis of key intermediates towards various natural products has been achieved.

The Swern oxidation of various indolic substrates is described, and a range of products resulting from overalloxidation at the 2-position were observed. In particular, depending on the substrate and reaction conditions, it was possible to achieve direct oxidation to α,β-unsaturated systems at the 2-position, to introduce a nucleophile at the 2-position, and to introduce a CH3-S-CH2 group at the indole 4-position via an unprecedented rearrangement of a Swern intermediate.

We report the preparation of polyfluoroalkyl aldehydes R F (CH 2 ) n CHO in high yields by direct oxidation of polyfluoroalkyl alcohols; the Swern oxidation, pyridinium chlorochromate and Dess-Martin periodinane are used and compared

2,3,4,6-Tetra- O -benzyl-hexos-5-uloses derived from d -glucose, d -mannose and d -galactose have been cyclized to cis -diols by a one pot Swern oxidation/SmI 2 -mediated pinacol coupling procedure. The effect of the substituent orientation on the diastereoselectivity of the coupling step is examined.

An efficient utilisation of RCM leading to a convenient synthesis of a pentacyclic indole alkaloid is described.

The syntheses of five new mixed azine-azole binucleating ligands are described. © 2007 Elsevier Science. All rights reserved We have long been interested in the synthesis and study of new bridging heterocyclic ligands and their use in coordination and metallosupramolecular chemistry. For example, we have recently reported investigations of binuclear metal complexes of ligands such as 1-5 (Scheme 1). Within this context, we showed that the binuclear ruthenium(II) complexes of ligands 1-4 exhibit unusually strong metal-metal interactions, seemingly mediated by the existence of the central azole ring. In order to probe the origin of this intriguing phenomenon, we have prepared a number of structurally related ligands, the syntheses of which we now report. Scheme 1. Previously reported binucleating ligands. In view of the intense current interest in the use of tridentate ligands related to 2,2’,6’,2”-terpyridine, we decided to prepared analogues of 3 and 4 with tridentate binding domains. A key synthon for such compounds is 2,2’-bipyridine-6-carboxaldehyde 6, which has previously been prepared by methylation of 2,2’-bipyridine and selenium dioxide oxidation, and by Swern oxidation of the hydroxymethyl derivative. We have found that this compound is more conveniently prepared by the sequence shown in Scheme 2. Thus 2,2’-bipyridine was converted to the 6-bromo-derivative by a methylation, oxidation, bromination sequence and then converted into 6 by lithium ______________________

In order to establish a mild conversion method of primary amides to nitriles, various types of carboxamides were treated under Swern oxidation conditions, (COCl)2-DMSO and Et3N, as a dehydrating agent to obtain desired nitriles in 75–96% yields.

Swern oxidation of β-amino alcohols containing tertiary amino groups afforded the corresponding α-amino carbonyl compounds in fair to excellent yield. Yields were dependent on the steric requirement of the amine base used for the reaction and were optimized by the use of N-methylpyrrolidine, N-ethylpiperidine, or triethylamine, depending on the β-amino alcohol substrate.

A new approach for the asymmetric synthesis of blastidic acid, the β-amino acid component of the antibiotic, (+)-blasticidin S has been achieved in 11 steps and 30% overall yield. The key transformations involve a one-pot Swern/Wittig reaction sequence to prepare the carbon backbone followed by a stereoselective conjugate addition to introduce the β-amino functionality.

A mild method for the deoxygenation of α-hydrogen-containing sulfoxides to sulfides is reported. This synthetically useful and operationally simple protocol derives mechanistically from the Swern oxidation methodology.

Using a copper-catalyzed coupling reaction of amino acid and aryl halide, followed by intramolecular cyclization of N -aryl-1-hydroxyl-3-propylamines under the Swern’s condition as the key steps, ( S )-2-hydroxymethyl-1,2,3,4-tetrahydroquinoline was synthesized as an example of optically pure 2-functionalized 1,2,3,4-tetrahydroquinolines.

Reductive alkylation is a practical strategy for a total synthesis of spider toxin argiotoxin 636, a polyamine amide which is a selective glutamate receptor antagonist and may have potential as a neuroprotective agent. Central to this synthesis are a Swern oxidation and a reductive alkylation.

The synthesis of optically active 2H-azirine-2-carboxylic esters was achieved by Swern oxidation of the corresponding aziridine-carboxylic esters. For both trans and cis aziridine esters this oxidation gives a regioselective introduction of the double bond which is not in conjugation with the ester function. The methyl ester of ent-Azirinomycin was prepared in this manner.

The reaction of 2,3-dimethylcyclohexan-1-one (2) with the functionalized allylic bromide 3 produced regio- and strereoselectively a precursor (4) of the new sesquiterpenoid sollasin a / fulvanin 1 (1). Functional group transformations then completed the synthesis.

An efficient synthesis of new imidazo[1,2-b]pyridazine derivatives was effected by treating 3,6-dichloropyridazine with various 2-hydroxyethylamines following by imidazole ring formation under Swern oxidative conditions. Some mechanistic aspects of the cyclization step are discussed.

The structural revision of the product of the tandem aldol - Swern oxidation process to β—triketones is reported. Further oxidation of products leading to the corresponding diketones (ex. 4, 5) was observed. The properties of the β—triketone are also described.

New odorless protocols for the Swern oxidation as well as the Corey–Kim oxidation using dodecyl methyl sulfoxide ( 1 ) or dodecyl methyl sulfide ( 3 ) are described.

Attempts to synthesise chiral sulfide 1 from the dimesylate precursor 5 , via a cyclisation reaction using sodium sulfide in dimethyl sulfoxide, led to the unexpected formation of an unsymmetrical furan derivative 8 . Studies were made into the effect of changing the leaving group, and changing the solvent of reaction. The desired compound could be synthesised in good yields from the xanthate 9 using a radical-mediated procedure.

The Baylis–Hillman adducts of aryl aldehydes and alkyl acrylates are efficiently oxidized to the corresponding α-methylene-β-keto esters with the Dess–Martin periodinane. The attempted Swern oxidation of the same adducts resulted in SN2′-type substitution of the allylic hydroxyl group by chloride.

Sodium erythorbate ( 7 ) has been converted to loracarbef ( 1 ). Oxidation of sodium erythorbate to D -erythronolactone ( 8 ) followed by selective monotosylation and treatment with sodium ethoxide provided ethyl (2 S ,3 R )-4-hydroxy-2,3-epoxybutyrate ( 10 ). Swern oxidation of this epoxide into the aldehyde ( 11 ), imine formation with tert -butylglycinate and an enantioselective Staudinger reaction with phthalimidoacetyl chloride afforded the (3 S ,4 S )- cis - β-lactam ( 13 ). Appropriate functional group manipulations followed by a Dieckmann condensation, chlorination, and protecting group removals gave the enantiomerically pure nucleus of loracarbef ( 24 ).

Carbamate protected alkylhydrazines have been found to oxidize cleanly to the corresponding hydrazone under Swern conditions. The reaction works on hydrazines with primary, secondary, and branched alkyl groups.

Swern oxidation of 8,16-dimethoxy- and 8,16-dimethyl-5,13-di-t-butyl-1,2,9,10-tetrahydroxy[2.2]metacyclophane, 1 and 2, afforded 5,13-di-t-butyl-10-hydroxy-8,16-dimethoxy[2.2]metacyclophane-1,2,9-trione 3 and 4. By subsequent oxidation with DDQ, 8,16-dimethoxy- and 8,16-dimethyl-5,13-di-t-butyl[2.2]metacyclophane-1,2,9,10-tetraones, 5 and 6, were obtained.

The Swern oxidation of structurally diverse alcohols (3,4,7, and11) employing the oxalyl chloride-DMSO protocol unexpectedly gave rise to products resulting from concomitant electrophilic chlorination. This potential problem can be avoided either by using the reagents in stoichiometric amount or by employing trifluoroacetic anhydride-DMSO or acetic anhydride-DMSO.

Sharpless epoxidation of the readily available dienol 2 , followed by regiospecific opening with Me2CuLi/BF3·Et2O yields, after protecting group manipulation, the monoprotected diol 10c . Swern oxidation gives the cyclic carbaminol 14a which is easily manipulated to α-cyano oxazolidinone 15 and thus, by literature methods, to the title compound. Using this procedure, good overall yield and high enantiomeric purity are obtained.

Das aus Dimethylsulfoxid (I) und Trifluoracetanhydrid (II) bei -60°C gebildete Addukt (III) reagiert mit aromatischen Aminen, Amiden und Sulfonamiden (IV) in Ausbeuten von 60-80% zu Iminosulfuranen (V).

In the dimethyl sulfoxide (DMSO)-metal oxide oxidation of alcohol to carbonyl compound, molybdenum oxides were the only useful catalytic reagents, and various alcohols were oxidized to the corresponding carbonyl compounds in high yields.

The regioselective reductive demethylation of the O-methyldiosphenol functionality in the A ring of quassin (3) with chlorotrimethylsilane and sodium iodide furnished picrasin B (1). Swern oxidation of 1 furnished Δ 2 -picrasin B (2), and O-methylation of 2 regenerated quassin (3).