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Spectroscopic identification of the nickel acylate complex
NMR and IR spectral data of the pentanoyl nickelate complex are presented and are consistent with a mononuclear nickel complex. This nickel acylate complex is thermally stable in THF at ambient temperature (+20°C) for prolonged periods (24 h) but decomposes rapidly in air.
Simunic, Joan L.,Pinhas, Allan R.
p. 1358 - 1360
(1987)
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Asymmetric Catalytic Epoxidation of Terminal Enones for the Synthesis of Triazole Antifungal Agents
An enantioselective epoxidation of α-substituted vinyl ketones was realized to construct the key epoxide intermediates for the synthesis of various triazole antifungal agents. The reaction proceeded efficiently in high yields with good enantioselectivities by employing a chiral N,N′-dioxide/ScIII complex as the chiral catalyst and 35% aq. H2O2 as the oxidant. It enabled the facile transformation for optically active isavuconazole, efinaconazole, and other potential antifungal agents.
Feng, Xiaoming,He, Qianwen,Liu, Xiaohua,Zhang, Dong,Zhang, Fengcai
supporting information
p. 6961 - 6966
(2021/09/11)

Sulfonium ion-promoted traceless Schmidt reaction of alkyl azides
Schmidt reaction by sulfonium ions is described. General primary, secondary, and tertiary alkyl azides were converted to the corresponding carbonyl or imine compounds without any trace of the activators. This bond scission reaction through 1,2-migration of C-H and C-C bonds was accessible to the one-pot substitution reaction.
Ardiansah, Bayu,Kakiuchi, Kiyomi,Morimoto, Tsumoru,Tanimoto, Hiroki,Tomohiro, Takenori
p. 8738 - 8741
(2021/09/08)

C-H Alkylation of Aldehydes by Merging TBADT Hydrogen Atom Transfer with Nickel Catalysis
Catalyst controlled site-selective C-H functionalization is a challenging but powerful tool in organic synthesis. Polarity-matched and sterically controlled hydrogen atom transfer (HAT) provides an excellent opportunity for site-selective functionalization. As such, the dual Ni/photoredox system was successfully employed to generate acyl radicals from aldehydes via selective formyl C-H activation and subsequently cross-coupled to generate ketones, a ubiquitous structural motif present in the vast majority of natural and bioactive molecules. However, only a handful of examples that are constrained to the use of aryl halides are developed. Given the wide availability of amines, we developed a cross-coupling reaction via C-N bond cleavage using the economic nickel and TBADT catalyst for the first time. A range of alkyl and aryl aldehydes were cross-coupled with benzylic and allylic pyridinium salts to afford ketones with a broad spectrum of functional group tolerance. High regioselectivity toward formyl C-H bonds even in the presence of α-methylene carbonyl or α-amino/oxy methylene was obtained.
Murugesan, Vetrivelan,Ganguly, Anirban,Karthika, Ardra,Rasappan, Ramesh
p. 5389 - 5393
(2021/07/21)

A simple synthesis of ketone from carboxylic acid using tosyl chloride as an activator
An effective process for the conversion of carboxylic acid to ketone has been discovered. In this process, carboxylic acid has been activated using p-toluene sulphonyl group. Under the optimized condition, aromatic, aliphatic heteroaromatic carboxylic acids have been proved to be good substrates for this methodology. The byproduct of this reaction can be removed very easily during work up process. Also, one equivalent of organometallic reagent is sufficient to complete this transformation.
Jana, Samaresh,Sahoo, Debasis,Sarkar, Sohini
supporting information

(2019/09/06)

Simple one pot synthesis of ketone from carboxylic acid using DCC as an activator
Simple one pot procedure for the conversion of carboxylic acid to ketone is described. Various carboxylic acids were converted to the corresponding ketones in excellent manner in presence of N,N′-dicyclohexylcarbodiimide (DCC) and organometallic reagents. Aromatic, heteroaromatic and aliphatic acids were converted to the corresponding ketones smoothly under the optimum conditions using organolithium reagents. In this process, desired products have been isolated from the crude reaction mixtures in moderate yields during the purification process.
Mekonnen, Habtamu Gelaw,Jana, Samaresh
supporting information
p. 1382 - 1384
(2019/04/30)

Rational Design of a Metallocatalytic Cavitand for Regioselective Hydration of Specific Alkynes
The synthesis of a functionalized supramolecular cavitand with inwardly oriented AuI and P=O moieties was explored, including its catalytic proclivity in the selective hydration of internal alkynes. The cavitand works as a supramolecular flask device: AuI coordinates to the triple bond, the P=O moiety connects with a H2O molecule, and the cavity favors folding of a single alkynyl side chain. Several tests of different substrate patterns indicated that the cavity was substrate specific, similar to enzymatic catalysis.
Endo, Naoki,Inoue, Mami,Iwasawa, Tetsuo
supporting information
p. 1136 - 1140
(2018/03/13)

Synthesizing method of alpha-arone or alpha-hetero-arone
The invention discloses a synthesizing method of alpha-arone or alpha-hetero-arone and belongs to the technical field of metal organic catalyzing. The synthesizing method has the advantages that a terminal alkynyl compound, oxynitride and a proton supply agent is catalyzed by univalence metal salt to obtain N-O pyridine oxynitride enol salt, purification and separation are not needed, and the N-Opyridine oxynitride enol salt is allowed to have reaction with arene and hetero-arene in a one-pot manner to obtain the alpha-arone or alpha-hetero-arone; the method is high in functional group tolerance, wide in substrate application range, high in yield, simple and easy to operate and easy in final product separation and purification.
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Paragraph 0064-0066

(2018/09/08)

Regioselective Arene and Heteroarene Functionalization: N-Alkenoxypyridinium Salts as Electrophilic Alkylating Agents for the Synthesis of α-Aryl/α-Heteroaryl Ketones
A direct regioselective functionalization of arenes and heteroarenes using N-alkenoxypyridinium salts as electrophilic alkylating agents for the synthesis of α-aryl/heteroaryl ketones has been developed. The method generates alkylating agents from alkynes and N-pyridine oxide followed by site-selective electrophilic substitution with a broad range of arenes and heteroarenes including benzene derivates, phenols, ethers, indoles, pyrroles, furans, and thiophenes in one pot. Kinetic isotope effect measurements and DFT studies reveal that this reaction likely proceeds through a carbon-cation intermediate.
Zhai, Rong L.,Xue, Yun S.,Liang, Ting,Mi, Jia J.,Xu, Zhou
p. 10051 - 10059
(2018/07/30)

Design of a novel thiophene inhibitor of 15-lipoxygenase-1 with both anti-inflammatory and neuroprotective properties
The enzyme 15-lipoxygenase-1 (15-LOX-1) plays a dual role in diseases with an inflammatory component. On one hand 15-LOX-1 plays a role in pro-inflammatory gene expression and on the other hand it has been shown to be involved in central nervous system (CNS) disorders by its ability to mediate oxidative stress and damage of mitochondrial membranes under hypoxic conditions. In order to further explore applications in the CNS, novel 15-LOX-1 inhibitors with favorable physicochemical properties need to be developed. Here, we present Substitution Oriented Screening (SOS) in combination with Multi Component Chemistry (MCR) as an effective strategy to identify a diversely substituted small heterocyclic inhibitors for 15-LOX-1, denoted ThioLox, with physicochemical properties superior to previously identified inhibitors. Ex?vivo biological evaluation in precision-cut lung slices (PCLS) showed inhibition of pro-inflammatory gene expression and in?vitro studies on neuronal HT-22?cells showed a strong protection against glutamate toxicity for this 15-LOX-1 inhibitor. This provides a novel approach to identify novel small with favorable physicochemical properties for exploring 15-LOX-1 as a drug target in inflammatory diseases and neurodegeneration.
Eleftheriadis, Nikolaos,Poelman, Hessel,Leus, Niek G.J.,Honrath, Birgit,Neochoritis, Constantinos G.,Dolga, Amalia,D?mling, Alexander,Dekker, Frank J.
p. 786 - 801
(2016/08/30)

Internal Alkyne Regio- and Chemoselectivity using a Zwitterionic N-Heterocyclic Carbene Gold Catalyst in a Silver-Free Alkyne Hydration Reaction
An alkyne hydration of terminal and internal alkynes is reported using a zwitterionic N-heterocyclic carbene gold catalyst [(BNHC)Au(SMe2)] in the absence of silver and Br?nsted acid additives. The hydration demonstrates good regioselectivity in alkyne hydration and chemoselectivity for internal alkynes vs. terminal. In addition, (BNHC)Au(SMe2) performs a propargyl alcohol hydration to predominantly form α-hydroxymethyl ketone over the more common Meyer–Schuster rearrangement product. While complex (BNHC)Au(SMe2) is active without silver additives, addition of silver hexafluoroantimonate (AgSbF6) increases reaction rate and decreases selectivity for internal alkyne hydration over terminal substrates. To the best of our knowledge, the rate enhancement of (BNHC)Au(SMe2) by AgSbF6is the first such demonstration of a silver effect for a “halide-free” Au catalyst. (Figure presented.).
Weerasiri, Kushan C.,Chen, Danmin,Wozniak, Derek I.,Dobereiner, Graham E.
p. 4106 - 4113
(2016/12/30)

A convenient catalytic oxidative 1,2-shift of arylalkenes for preparation of α-aryl ketones mediated by NaI
Using a catalytic amount of NaI and a stoichiometric oxidant Oxone@, a convenient procedure has been developed for the catalytic oxidative 1,2-shift of arylalkenes in CH3CN/H2O at room temperature, which provides the corresponding α-aryl ketones in moderate to good yields. In this protocol, sodium iodide is first oxidized into hypoiodous acid, which reacts with arylalkene to afford iodohydrin. Then, the iodohydrin is transformed into the α-aryl ketone via an oxidative 1,2-shift rearrangement.
Zhu, Min,Zhao, Yang
p. 248 - 250
(2015/03/30)

Silver-free two-component approach in gold catalysis: Activation of [LAuCl] complexes with derivatives of copper, zinc, indium, bismuth, and other lewis acids
Complexes of type [LAuCl] (L=phosphine, phosphite, NHC and others) are widely employed in homogeneous catalysis, however, they are usually inactive as such and must be used jointly with a halide scavenger. To date, this role has mostly been entrusted to silver salts (AgSbF6, AgPF6, AgBF4, AgOTf, etc.). However, silver salts can be the source of deactivation processes or side reactions, so it is sometimes advisable to use silver-free cationic gold complexes, which can be difficult to synthesize and to handle compared with the more robust chloride. We show in this study that various Lewis acids of the transition and main group metal families are expedient substitutes to silver salts. We have tested CuI, Cu II, ZnII, InIII, SiIV, Bi III, and other salts in a variety of typical AuI-catalyzed transformations, and the results have revealed that [LAuCl] can form active species in their presence. Not just silver: Active gold species have been generated from the corresponding inactive chlorides by using Lewis acids that are not typical in gold chemistry (see figure). Instead of silver salts, complexes of Cu, Zn, In, Si, Bi, and others have been used. This study shows that silver salts, which can cause deactivation processes and side reactions, can be replaced by various activators. Thus, the use of a sensitive cationic gold complex can be avoided.
Fang, Weizhen,Presset, Marc,Guerinot, Amandine,Bour, Christophe,Bezzenine-Lafollee, Sophie,Gandon, Vincent
p. 5439 - 5446
(2014/05/20)

Cyanocuprates convert carboxylic acids directly into ketones
Carboxylic acids were converted directly in 56-99% yields into methyl, n-butyl, and isopropyl ketones using excess cyanocuprates R2CuLi 3 LiCN. A substrate with a stereocenter α to the carboxylic acid was converted into ketones with very little loss of enantiomeric purity. A variety of functional groups were tolerated including aryl bromides. This direct transformation of a carboxylic acid into ketone with minimal tertiary alcohol formation is proposed to involve a relatively stable copper ketal tetrahedral intermediate.
Genna, Douglas T.,Posner, Gary H.
supporting information; experimental part
p. 5358 - 5361
(2011/12/15)

Photo-driven anti-Markovnikov alkyne hydration in self-assembled hollow complexes
Under UV-light irradiation, the anti-Markovnikov hydration of internal arylalkynes proceeds in the cavity of an electron-deficient coordination cage to give benzyl ketones; the reaction is triggered by cage-mediated, photo-induced electron transfer from the alkynes to the cage.
Murase, Takashi,Takezawa, Hiroki,Fujita, Makoto
supporting information; experimental part
p. 10960 - 10962
(2011/11/13)

Regio- And stereoselective intermolecular hydroalkoxylation of alkynes catalysed by cationic gold(I) complexes
Vinyl ethers and ketals are obtained from the reaction of phenylacetylene derivatives and dimethyl acetylenedicarboxylate (DMAD) with alcohols in good yields and levels of stereoselectivity by using cationic gold(I)-phosphine complexes as catalysts. By choosing the appropriate phosphine, the selective formation of the Z or the E isomer of the vinyl ether can be tuned, and the undesired formation of the ketal can be controlled. The isomerisation of fumarates (Z-isomer) to maleates (E-isomer) is a gold-catalysed process that can be conducted in onepot. When using polyols, 5-membered cyclic ketals are easily isolated by extraction with hexane and the gold complex can be reused.
Corma, Avelino,Ruiz, Violeta R.,Leyva-Perez, Antonio,Sabater, Maria J.
supporting information; experimental part
p. 1701 - 1710
(2010/10/04)

Reusable gold(I) catalysts with unique regioselectivity for intermolecular hydroamination of alkynes
Two gold(I) phosphine complexes bearing the low-coordinating bis(trifluoromethanesulfonyl)- imidate ligand, namely AuSPhosNTf2 and AuPPh3NTf2, are active catalysts for the regioselective intermolecular hydroamination of both internal and terminal alkynes under mild reaction conditions. The catalysts show a regioselectivity based on electronic rather than steric factors, which allow the preferential synthesis of regioisomers opposite to those described previously. This subtle chemo- and regiose-lectivity depends on the catalyst, substrates and reaction conditions employed, and allows one to perform new tandem reactions. These gold(I) complexes operate under free-solvent conditions, without exclusion of air, without addition of acidic promoters and can be quantitatively recovered and reused by simple precipitation in hexane.
Leyva, Antonio,Corma, Avelino
supporting information; experimental part
p. 2876 - 2886
(2010/03/25)

4,5 Dihydro-(1H)-Pyrazole Derivatives as Cannabinoid CB1 Receptor Modulators
The invention is directed to 4,5-dihydro-(1H)-pyrazole (pyrazoline) derivatives as cannabinoid CB1 receptor modulators, to pharmaceutical compositions comprising these compounds, to methods for their syntheses, to methods for preparing novel intermediates useful for their syntheses, and to methods for preparing compositions. The invention also relates to the uses of compounds and compositions administered to patients to achieve a therapeutic effect in multiple sclerosis, traumatic brain injury, pain including chronic pain, neuropathic pain, acute pain and inflammatory pain, osteoporosis, appetite disorders, epilepsy, Alzheimer's disease, Tourette's syndrome, cerebral ischaemia, emesis, nausea, and gastrointestinal disorders. Compounds of the present disclosure are directed to formula (I): wherein the substituents have the definitions given in the specification.
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Page/Page column 9

(2009/01/24)

Aquapalladium complex: A stable and convenient catalyst for the intermolecular hydroamination of alkynes
The intermolecular hydroamination of alkynes proceeds very smoothly in the presence of a catalytic amount of the aquapalladium complex [Pd(dppe)(H 2O)2](TfO)2. This reaction most probably proceeds through the formation of an equilibrium between the hydroxopalladium and the amidopalladium complexes, and subsequent aminopalladation of alkynes. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
Shimada, Tomohiro,Bajracharya, Gan B.,Yamamoto, Yoshinori
p. 59 - 62
(2007/10/03)

Oxidative rearrangements of arylalkenes with [hydroxy(tosyloxy)iodo]benzene in 95% methanol: A general, regiospecific synthesis of α-aryl ketones
The treatment of arylalkenes with [hydroxy(tosyloxy)iodo]benzene in 95% methanol affords the corresponding α-aryl ketones. This oxidative rearrangement is general for acyclic and cyclic arylalkenes and permits regioselective syntheses of isomeric α-phenyl ketone pairs.
Justik, Michael W.,Koser, Gerald F.
p. 6159 - 6163
(2007/10/03)

Design, synthesis, and development of novel caprolactam anticonvulsants
Epilepsy afflicts 1-2% of the world's population and often goes untreated; nearly 70% of those with a form of epilepsy fail to receive proper treatment. Therefore, there is great demand for the design of novel, effective anticonvulsants to combat epilepsy in its numerous forms. Previously, α-hydroxy-α-phenylcaprolactam was found to have rather potent antiepileptic activity [anti-maximal electroshock (MES) ED50=63 mg/ kg and anti-subcutaneous Metrazol (scMet) ED50=74 mg/kg] when administered intraperitoneally in mice. We focused our attention on the development of this compound through traditional medicinal chemistry techniques - including the Topliss approach, isosteric replacement, methylene insertion, and rigid analogue approach - in the hopes of determining the effect of caprolactam α-substitution and other structural modifications on anticonvulsant activity. A number of the desired targets were successfully synthesized and submitted to the Anticonvulsant Screening Program of the National Institute of Neurological Disorders and Stroke (NINDS). Phase I results were quite promising for at least three of the compounds: α-ethynyl-α-hydroxycaprolactam (10), α-benzyl-α-hydroxycaprolactam (11), and α-hydroxy-α-(phenylethynyl)caprolactam (13). Phase II results for 11 strongly suggested it as a new structural class for further development, as it exhibited an anti-MES T.I. in excess of 4.0. Further, the potent activity of 13 in all models also pointed to the substituted alkynylcaprolactams as a new anticonvulsant structural class.
Grimm, Jonathan B.,Stables, James P.,Brown, Milton L.
p. 4133 - 4141
(2007/10/03)

Substituted isoxazoles for the treatment of inflammation
A class of substituted isoxazolyl compounds is described for use in treating inflammation and inflammation-related disorders. Compounds of particular interest are defined by Formula (III) wherein R7 is selected from hydroxyl, lower alkyl, carboxyl, halo, lower carboxylalkyl, lower alkoxycarbonylalkyl, lower alkoxyalkyl, lower carboxyalkoxyalkyl, lower haloalkyl, lower haloalkylsulfonyloxy, lower hydroxyalkyl, lower aryl (hydroxylalkyl), lower carboxyaryloxyalkyl, lower alkoxycarbonylaryloxyalkyl, lower cycloalkyl, lower cycloalkylalkyl, and lower aralkyl; and wherein R8 is one or more radicals independently selected from hydrido, lower alkylsulfinyl, lower alkyl, cyano, carboxyl, lower alkoxycarbonyl, lower haloalkyl, hydroxyl, lower hydroxyalkyl, lower haloalkoxy, amino, lower alkylamino, lower arylamino, lower aminoalkyl, nitro, halo, lower alkoxy, aminosulfonyl, and lower alkylthio; or a pharmaceutically-acceptable salt thereof.
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Page 38

(2010/11/30)

Palladium-catalyzed intermolecular hydroamination of alkynes: A dramatic rate-enhancement effect of o-aminophenol
The hydroamination of alkynes using o-aminophenol proceeds in very high to good yields in the presence of Pd(NO3)2 catalyst. Remarkable rate enhancement with o-aminophenol is presumably due to the chelation effect of the ortho OH group to palladium. Copyright
Shimada, Tomohiro,Yamamoto, Yoshinori
p. 12670 - 12671
(2007/10/05)

Titanocene(II)-promoted desulfurizative acylation of thioacetals with alkanenitriles
Ketones were obtained in good yields by titanocene(II)-promoted reaction of thioacetals with alkanenitriles. The regioselective formation of α-substituted ketone was observed when the reaction was carried out in the presence of methyl iodide or benzyl bro
Takeda, Takeshi,Taguchi, Haruhiko,Fujiwara, Tooru
p. 65 - 68
(2007/10/03)

PHENYLPROPENONE COMPOUNDS AND MEDICINES CONTAINING THE SAME
This invention relates to compounds represented by the following formula (1) or (2) and also to medicines containing the same. wherein R1, R2 and R3 each independently represent an alkyl group or the like, R4 represents an alkyl group, an alkoxyl group or the like, and -N(R5)R6 represents a substituted phenyl amino group, a substituted phenylpiperazinyl group or the like. These compounds are useful as prophylatic and therapeutic agents for human arteriosclerosis, as they have strong ACAT inhibitory activity, lower the concentration of cholesterol in blood and inhibit accumulation of cholesterol.
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(2008/06/13)

Synthesis of α,β-unsaturated ketone from α-iodo ketone using photoirradiation
Irradiation of α-iodo ketone in hexane under a nitrogen atmosphere with a high-pressure mercury lamp (λ>300nm) at room temperature afforded the corresponding α,β-unsaturated ketones in good yield. This reaction affords a new, clean and convenient synthetic method for the α,β-unsaturated ketone.
Ji, Shun-Jun,Takahashi, Eiji,Takahashi, T. Tomoyoshi,Horiuchi, C. Akira
p. 9263 - 9266
(2007/10/03)

Syntheses of Dialkyl and Functionalized Ketones via 1-(Benzotriazol-1-yl)alkyl Methyl Thioethers
Benzotriazol-1-ylmethyl methyl thioether (1), after easy deprotonation by BuLi, reacted with alkyl halides to afford 1-(benzotriazol-1-yl)alkyl methyl thioethers 2 in good yields. The utility of compounds 2 as alkanoyl anion equivalents was demonstrated by the reactions of their anions with alkyl halides, aldehydes, ketones, esters, and phenyl isocyanate: the products were readily hydrolyzed to α-functionalized ketones in dilute aqueous acid.
Katritzky, Alan R.,Oniciu, Daniela C.,Ghiviriga, Ion,Soti, Ferenc
p. 2110 - 2115
(2007/10/03)

Synthesis of carbonyl and dicarbonyl compounds from organometallic reagents and N-imidazolium-N-methyl amides and bis-amides
A new method for the synthesis of selective acylating agents is described from the reaction of carboxylic acids with 3-methyl-1-methylamino-3H-imidazol-1-ium salts in the presence of appropriate coupling reagents. The amides and bis-amides thus prepared reacted selectively with organometallics to afford ketones and diketones and with DIBALH to give aldehydes and dialdehydes in high yields.
De Las Heras, Maria A.,Vaquero, Juan J.,Garcia Navio, Jose L.,Alvarez-Builla, Julio
p. 14297 - 14310
(2007/10/03)

Cerium(III) chloride remarkably increases the rates of formation and yields of ketones in the reaction of lithium carboxylates with organolithiums
The presence of CeCl3 greatly increases the yield of ketones in the reaction of organolithiums with lithium carboxylates. The CE(III) suppresses the enolization of the lithium carboxylate, previously unrecognized as a competing reaction except in special cases, and the formation of tertiary alcohols. One of the reasons for the latter effect is a surprising increase in the rate of addition of the organometallic to the lithium carboxylate in the presence of Ce(III).
Ahn, Yoonmo,Cohen, Theodore
p. 203 - 206
(2007/10/02)

Nitrogenous bicyclic derivatives substituted with benzyl
Novel bicyclic compounds in all possible racemic, enantiomeric and diasteroisomeric forms of the formula STR1 having antagonistic properties for angiotensin II receptors and novel intermediates and process for their preparation.
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(2008/06/13)

Hindered organoboron groups in organic chemistry. 24. The condensation of aliphatic aldehydes with dimesitylboron stabilised carbanions to give ketones
The condensation of boron stabilised carbanions, MeS2BCHLiR1, (R1≠H) with aliphatic aldehydes, R2CHO, followed by treatment with trifluoroacetic anhydride (TFAA) or N-chlorosuccinimide (NCS) is an unique, broadly applicable redox process that yields ketones, R1CH2COR2, directly and in high yields. The anion MeS2BCH2Li (MeS2BCHLiR1, R1=H) gives high yields of alkenes, R2CH=CH2 in the same conditions.
Pelter, Andrew,Smith, Keith,Elgendy, Said M. A.,Rowlands, Martin
p. 7104 - 7118
(2007/10/02)

Palladium(0)-catalyzed thioboration of terminal alkynes with 9-(alkylthio)-9-borabicyclo[3.3.1]nonane derivatives: Stereoselective synthesis of vinyl sulfides via the thioboration-cross-coupling sequence
Theaddition of 9-(alkylthio)-9-borabicyclo[3.3.1]nonanes(9-(RS)-9-BBN) 1 to terminal alkynes was catalyzed by Pd(PPh3)4 (3 mol %) to produce 9-[(Z)-2-(alkylthio)-1-alkenyl]-9-BBN derivatives 2 in high yields. The reactions were highly regio- and stereoselective, and their conditions were sufficiently mild that a variety of functionalized alkenylboranes 2 with defined stereochemistry were readily synthesized. The boranes 2 exhibited exceptionally high reactivity on protonolysis with methanol to produce the Markovnikov adducts of thiols to 1-alkynes, 2-(alkylthio)-1-alkenes 3. The synthetic utility of the present reaction was demonstrated by the regio- and stereoselective one-pot synthesis of alkenyl sulfides 7 via the palladium-catalyzed thioboration-cross-coupling sequence.
Ishiyama, Tatsuo,Nishijima, Koh-Ichi,Miyaura, Norio,Suzuki, Akira
p. 7219 - 7225
(2007/10/02)

Substituted (Carbazol-9-yl)(benzotriazol-1-yl)methanes: Novel Acyl Anion Equivalents
Alkyl(carbazol-9-yl)(benzotriazol-1-yl)methanes are deprotonated by BuLi to form anions which react with alkyl halides, aldehydes, and isocyanates to afford the expected products and which add 1,4 to α,β-unsaturated ketones.These products are hydrolyzed by dilute acid at ambient temperature to afford the corresponding ketones.
Katritzky, Alan R.,Yang, Zhijun,Lam, Jamshed N.
p. 6917 - 6923
(2007/10/02)

Reactions of Carbonyl Compounds with Grignard Reagents in the Presence of Cerium Chloride
The addition of Grignard reagents to ketones is significantly enhanced by cerium chloride with remarkable supression of side reactions, particularly enolization.Some esters, which are prone to side reactions, also react readily with Grignard reagents in the presence of cerium chloride to give normal reaction products in reasonable to high yields.
Imamoto, Tsuneo,Takiyama, Noboyuki,Nakamura, Kimikazu,Hatajima, Toshihiko,Kamiya, Yasuo
p. 4392 - 4398
(2007/10/02)

HINDERED ORGANOBORON GROUPS IN ORGANIC SYNTHESIS. 13. THE DIRECT PRODUCTION OF KETONES FROM ALIPHATIC ALDEHYDES BY A UNIQUE VARIANT OF THE BORON-WITTIG REACTION
In the presence of trifluoroacetic anhydride or N-chlorosuccinimide, aliphatic aldehydes react with dimesitylboron stabilised carbanions to give after work up, the corresponding ketones, a process wich is unique among Wittig type reactions.Yields of ketones are satisfactory in all cases except those involving the anion derived from the parent compound dimesitylmethylborane, wich give the corresponding alkenes.
Pelter, Andrew,Smith, Keith,Elgendy, Said,Rowlands, Martin
p. 5643 - 5646
(2007/10/02)

Methyl Group Migration in the Reactions of Alkynyltrialkylborates
It is shown that the methyl group cannot be used as a cheap, non-migrating group in the reactions of alkynyltrialkylborates with electrophiles.However, trimethylborane can be used as a methylboronating agent for alkynes, given the right choice of solvent, and this may be of use in terpene synthesis.
Pelter, Andrew,Drake, Robert A.
p. 4181 - 4184
(2007/10/02)

Formation of a Novel Acyl Anion Equivalent by the Electroreduction of Oxazolinium Salts
Electroreduction of oxazolinium salts synthesized from the corresponding carboxylic acids gave a novel acyl anion equivalent (AAE).The reaction of these AAEs with electrophiles afforded the corresponding aldehydes or ketones in good yields.
Shono, Tatsuya,Kashimura, Shigenori,Yamaguchi, Yoshihide,Ishige, Osamu,Uyama, Hiroshi,Kuwata, Fumitaka
p. 1511 - 1512
(2007/10/02)

AZO ANIONS IN SYNTHESIS. PT 1. t-BUTYLHYDRAZONES AS ACYL-ANION EQUIVALENTS
The lithium salts of aldehyde t-butylhydrazones react with electrophiles (aldehydes, ketones, alkyl halides, crotonates) to form C-trapped t-butylazo-compounds; tautomerisation and hydrolysis gave α-hydroxy ketones, ketones, and γ-keto esters in good yield, thereby providing a convenient new acyl-anion equivalent.Reaction of these lithium salts with aldehydes and ketones, followed by elimination provided a new route to azo alkenes.
Baldwin, Jack E.,Adlington, Robert M.,Bottaro, Jeffrey C.,Kolhe, Jayant N.,Perry, Matthew W. D.,Jain, Ashok U.
p. 4223 - 4234
(2007/10/02)

HYPERVALENT IODINE AS GOOD LEAVING GROUP: OXIDATIVE REARRANGEMENT OF 1-IODO-2-METHOXY-2-ARYLALKANES.
A new example of the good leaving group properties of hypervalent iodine is reported: oxidative rearrangement of 1-iodo-2-methoxy-2-arylalkanes 1 (R=alkyl) provides, via 1,2-aryl shift, alkyl benzyl ketones 3 in good yields.
Citterio, Attilio,Gandolfi, Marco,Giordano, Claudio,Castaldi, Graziano
p. 1665 - 1666
(2007/10/02)

GENERAL RELATIONSHIPS IN THE OPENING OF THE OXIRANE RING DURING CLEAVAGE OF GLYCIDIC ACIDS
By investigation of the decarboxylation of 2,3-epoxy derivatives of acids with various structures it was shown that contrary to the existing theory about the essential opening of the β (C-O) bond in the oxirane ring there are many structural types of 2,3-epoxypropionic acids, in which opening of the α (C-O) bond in the oxirane ring occurs during decarboxylation.It was also shown that these two possible reaction paths can also arise during the decarboxylation of one 2,3-epoxypropionic acid.On the basis of the obtained data a general relationship is developed for theopening of the oxirane ring during the decarboxylation of 2,3-epoxypropionic acids with any structure, and this makes it possible to predict the structure of the obtained carbonyl compound.
Kuroyan, R. A.,Markosyan, A. I.,Engoyan, A. P.,Vartanyan, S. A.
p. 1709 - 1714
(2007/10/02)

Reactions of Primary Amines with Organolithium Compounds
Primary amines react under mild conditions with an excess of an organolithium compound to form imines and α-substituted primary amines.Frequently, N-alkylamines that result from the condensation of these products are also isolated.For example, reactions of PhCH2NH2 with RLi (R = n-Bu) in refluxing hexane furnish (after hydrolysis) PhCHRNH2, PhRC=O, PhRC=NCHRPh, and R2C=O.The organic group of the primary amine can be a primary, secondary, or tertiary alkyl group.A reaction scheme is proposed that has three types of steps: (1) Mono- and dilithiation of the primary ami ne by an organolithium compound (both lithiations generally at nitrogen). (2) Elimination from the mono- or dilithiated amine of lithium hydride or (when the alkyl group is tertiary) of the elements of an organolithium compound to produce an N-lithioimine. (3) Addition of an organolithium compound to the lithioimine to produce a new dilithiated amine.The scheme rationalizes both the structures of the products and the effects of reaction conditions on product composition.Reaction of benzonitrile with an excess of n-butyllithium furnishes (after hydrolysis) di-n-butyl ketone as the major product.Since this reaction must also proceed through an N-lithioimine, formation of this product provides additional evidence for the proposed addition and elimination steps.
Richey, Herman G.,Erickson, Wayne F.
p. 4349 - 4357
(2007/10/02)

EFFETS POLAIRES DANS LES REACTIONS DE TRANSFERT HOMOLYTIQUE INTRAMOLECULAIRE D'HYDROGENE
In this paper we analyse the influence of a phenyl substituent on the relative rates of the 1-5 and 1-6 intramolecular hydrogen transfers.Compared to the abstraction of an aliphatic H atom, the activation energy for the abstraction of a benzylic H atom is smaller.The effect is nevertheless more important with a primary alkyl radical (1,3 kcal/mole) than with an alkoxy radical (0,9 kcal/mole).This can be analysed in terms of a polar effect.In addition, the size of the effect is too small to make a short distance transfer of a H atom feasible; this is in keeping with the statement that H atom migration requires a linear transition state.
Lefort, D.,Nedelec, J. Y.
p. 2681 - 2686
(2007/10/02)

A Reinvestigation of the Pictet-Gams Isoquinoline Synthesis. Part 2. Formation of Rearranged Isoquinolines: the Δ2-Oxazoline-Isoquinoline Transformation
Cyclisation of a series of 2-substituted 2-acylamino-1-arylalkan-1-ols using phosphorus pentaoxide in refluxing decalin is shown to lead to rearranged, i.e. 4-substituted, isoquinolines in addition to the anticipated 3-substituted isomers.The products arise largely via 5-phenyl-Δ2-oxazoline intermediates and the formation of the rearranged isoquionolines from these intermediates is fully discussed.The pathway is not substantially altered when 2-benzamido-1-methoxy-1-phenylalkanes are cyclised.
Ardabilchi, Nasser,Fitton, Alan O.,Hadi, A. Hamid b. A.,Thompson, J. Robin
p. 1710 - 1725
(2007/10/02)

Reaction of Lithium Dialkylcuprates with S-2-Pyridiyl Thioates in the Presence of Oxygen. A Carboxylic Ester Synthesis
Reaction of lithium dialkylcuprates with S-2-pyridyl thioates in the presence of oxygen affords carboxylic esters in high yields, whereas under nitrogen it affords ketones.
Kim, Sunggak,Lee, Jae In,Chung, Bong Young
p. 1231 - 1232
(2007/10/02)

Electrooxidation of alcohols using a new double mediatory system
The electrochemical oxidation of alcohols was accomplished by using a double mediatory system in which both alkyl methyl sulfide and bromide act in concert as mediators.
Shono, Tatsuya,Matsumura, Yoshihiro,Hayashi, Jue,Mizoguchi, Mikiko
p. 1867 - 1870
(2007/10/02)