- Palladium-Catalyzed Asymmetric Hydrosulfonylation of 1,3-Dienes with Sulfonyl Hydrazides
-
A highly enantio- and regioselective hydrosulfonylation of 1,3-dienes with sulfonyl hydrazides has been realized by using a palladium catalyst containing a monodentate chiral spiro phosphoramidite ligand. The reaction provided an efficient approach to synthetically useful chiral allylic sulfones. Mechanistic studies suggest that the reaction proceeds through the formation of an allyl hydrazine intermediate and subsequent rearrangement to the chiral allylic sulfone product. The transformation of the allyl hydrazine intermediate to the product is the enantioselectivity-determining step.
- Li, Ming-Ming,Cheng, Lei,Xiao, Li-Jun,Xie, Jian-Hua,Zhou, Qi-Lin
-
p. 2948 - 2951
(2020/12/15)
-
- Efficient synthesis and biological evaluation of demethyl geranylgeranoic acid derivatives
-
Synthetic retinoids have generated in the fields of dermatology and oncology due to their potent anti-proliferative and differentiation activities. We efficiently synthesized different demethyl geranylgeranoic acid (GGA) analogs, and evaluated their biological activities. Among the demethyl analogs synthesized, 3-demethyl derivative exhibited the highest anti-proliferative activity in HL-60 cells. In addition, a 3-demethyl derivative induced apoptosis more potently than 9Z-retinoic acid. These activities were due to the high binding affinity of 3-demethyl derivative for retinoid receptors. We found that, in a conjugated polyene system combined with a methyl substituent, the position of the methyl played an important role in the regulation of gene transcription and apoptosis-inducing activity. These results provided useful information on the structure-activity relationships of GGA derivatives that function as acyclic retinoic acid analogs. This information is likely to be useful in the development of new anti-cancer drugs.
- Wada, Akimori,Wang, Fei,Suhara, Yoshitomo,Yamano, Yumiko,Okitsu, Takashi,Nakagawa, Kimie,Okano, Toshio
-
experimental part
p. 5795 - 5806
(2010/09/18)
-
- Aluminum chloride-iron promoted coupling of sulfonyl chlorides with alkyl halides in aqueous media
-
A simple and inexpensive procedure for the coupling of sulfonyl chlorides and alkyl halides with aluminum chloride-iron system at ambient temperature in high yield is achieved in aqueous media.
- Saikia, Promod,Laskar, Dhrubojyoti D.,Prajapati, Dipak,Sandhu, Jagir S.
-
p. 512 - 513
(2007/10/03)
-
- Bi or Cd-induced coupling of sulfonyl chlorides with allylic halides. A simple synthesis of allylic sulfones
-
The bismuth or cadmium-catalyzed coupling reaction between aryl and alkyl sulfonyl chlorides and allylic halides proceeds smoothly to provide excellent yields of allylic sulfones at ambient temperature.
- Baruah, Mukulesh,Boruah, Anima,Prajapati, Dipak,Sandhu, Jagir S.
-
p. 1083 - 1084
(2007/10/03)
-
- Palladium-Catalyzed Asymmetric Allylic Sulfonylation
-
The palladium-catalyzed asymmetric sulfonylation of allylic substrates rac-7a,b and rac-8a,b in the presence of the chiral phosphino-oxazoline ligand 3a gave the allylic sulfones 9a and 9b with ee-values of 59percent and 88percent, respectively, in high yield.In the presence of ligand ent-3b the enantiomeric allylic sulfones ent-9a and ent-9b were obtained with ee-values of 57percent and 93percent in high yield.
- Eichelmann, Holger,Gais, Hans-Joachim
-
p. 643 - 646
(2007/10/02)
-
- "Syn-Effect" in the Conversion of (E)-Vinylic Sulfones to the Corresponding Allylic Sulfones
-
It was found that (E)-vinylic sulfones preferentially afford (Z)-allylic sulfones as kinetically-controlled products by treatment with a base under mild conditions, while (Z)-vinylic sulfones give (E)-allylic sulfones.Such stereochemical relationship was
- Hirata, Takaki,Sasada, Yoshihiro,Ohtani, Takashi,Asada, Takahiro,Kinoshita, Hideki,et al.
-
-
- SH2' Type Reactions of Arenesulfonyl Chlorides with Allylic Compounds Catalyzed by a Ruthenium(II) Complex
-
In the presence of a catalytic amount of dichlorotris(triphenylphosphine)ruthenium(II), the reactions of arenesulfonyl chlorides with allyl phenyl sulfide and allyl phenyl selenide proceeded smoothly to give allyl phenyl sulfone in high yield as well as the corresponding diphenyl disulfide or diphenyl diselenide.An SH2'-type mechanism involving the arenesulfonyl radical is proposed.
- Kamigata, Nobumasa,Ishii, Kimiko,Ohtsuka, Takeshi,Matsuyama, Haruo
-
p. 3479 - 3481
(2007/10/02)
-
- Regio- and Stereoselective Synthesis of (E)- and (Z)-Allylsulfones from Aldehydes and Alkynes
-
Several (E)- and (Z)-1-p-toluenesulfonyl(=tosyl)-2-alkenes, allylsulfones, were regio- and stereoselectively prepared from aldehydes and alkynes, respectively, in good yields by application of the results of our previous investigation on "syn-effect" and
- Ozawa, Motoyasu,Iwata, Noriyoshi,Kinoshita, Hideki,Inomata, Katsuhiko
-
p. 1689 - 1692
(2007/10/02)
-
- Palladium-Catalyzed Allylic Sulfinate-Sulfone Rearrangements
-
Upon treatment with a zero-valent palladium catalyst, tetrakis(triphenylphosphine)palladium, in tetrahydrofuran under mild conditions allylic p-toluenesulfinates underwent α- or γ-rearrangements of the sulfonyl group via ionic intermediates to give allylic sulfones.The regiochemistry of the rearrangements depends on the character of the intermediary allylic cationic carbons generated and the steric hindrance involved therein.Keywords - allylic sulfinate; allylic sulfone; palladium catalyst; sulfinate-sulfone rearrangement; regiochemistry; tetrakis(triphenylphosphine)palladium.
- Hiroi, Kunio,Makino, Kunitaka
-
p. 1727 - 1737
(2007/10/02)
-
- Rearrangement of Some Allylic Sulphinate Esters to Allylic Sulphones. Ion-pair and Sigmatropic Shift Mechanisms
-
The mechanism of rearrangement of a number of allylic sulphinate esters to the corresponding allylic sulphones on heating in formamide has been investigated as a function of substrate structure.Simple systems such as crotyl and α-methylallyl-sulphinate ap
- Knight, Derek J.,Whitham, Gordon H.,Williams, Jonathan G.
-
p. 2149 - 2152
(2007/10/02)
-
- Convenient Methods for the Preparation of Vinylic and Allylic Sulfones from Alkenes, Haloalkanes, and Aldehydes. Stereochemistry of the Conversion of Vinylic Sulfones to the Corresponding Allylic Sulfones
-
1- or 2-p-Tolylsulfonyl(=tosyl)-1-alkenes, vinylic sulfones, were regioselectively prepared from 1-alkenes via iodosulfonization or sulfonylmercuration and also from 1-haloalkanes by the homologation or unhomologation methods.The vinylic sulfones thus prepared were further converted to the corresponding allylic sulfones under basic conditions.The stereochemistry of this conversion was discussed.One-carbon homologated allylic sulfones were directly obtained from aldehydes in good yields by the reaction with diethyl phenylsulfonylmethylphosphonate and 1,8-diazabicycloundec-7-ene (DBU) under mild conditions.
- Inomata, Katsuhiko,Sasaoka, Shin-ichi,Kobayashi, Toshifumi,Tanaka, Yuhji,Igarashi, Susumu,et al.
-
p. 1767 - 1780
(2007/10/02)
-
- 1,3-Rearrangements of Some Allylic Sulphones
-
The 1,3-rearrangement of a number of acyclic and cyclic allylic p-tolyl sulphones has been found to occur on treatment (a) with benzoyl peroxide (BPO) in CCl4 under reflux or (b) with sodium toluene-p-sulphinate in aqueous acetic acid at 110 deg C.Rearran
- Knight, Derek J.,Lin, Peter,Whitham, Gordon H.
-
p. 2707 - 2714
(2007/10/02)
-
- A 1,3-Rearrangement of Allylic Sulphones Caused by m-Chloroperbenzoic Acid and Sodium Hydrogen Carbonate
-
The reaction of allylic sulphones with m-chloroperbenzoic acid in the presence of aqueous sodium hydrogen carbonate can result in 1,3-allylic rearrangement or isomerisation of the double bond depending on the structure of the allylic sulphone.Subsequent e
- Kocienski, Philip
-
p. 945 - 948
(2007/10/02)
-
- Syntheses a l'aide de sulfones. XVIII. Utilisation des disulfones-1,1 pour la synthese stereoselective de composes olefiniques
-
2-Alkenyl-1,1-disulfones 4 are readily available in excellent yields by condensation of aldehydes with bisaryl or bisalkylsulfonylmethanes in the presence of piperidine acetate and molecular sieves at room temperature.A small amount of the 1-alkenyl isomer is also found when the aldehyde is α-substituted but it can be converted into the 2-alkenyl isomer by base catalysed equilibration.The 2-alkenyl-1,1-disulfones display only E geometry whereas E allylic monosulfones are difficult to isolate in a state of stereochemical purity (about 20percent of the Z isomer at equilibrium (8)).Alkylation is readily performed: treatment of 4 and 6 by sodium hydride in dimethylformamide and then by methyl iodide gives disulfones 5 E and 7 in 78-95percent yields.The alkylation of 4 (R=Et) by butyl iodide gives 70percent of 5 E(R=Et, R'=n-Bu) resulting from alkylation at the α position and 8percent of 3 (R=Et, R'=n-Bu) resulting from alkylation at the γ position.The α isomer is readily purified by crystallization.Reduction of disulfones 4 or 5 by aluminium amalgam leads quantitatively to allylic sulfones 2E or 8E.Olefins 9E are obtained upon total reduction of disulfones 4 or 5 by lithium in ethylamine at -78 deg C but in the case of disulfones 5 the olefins 9E are contaminated by isomers 10E and 10Z.
- Cuvigny, Therese,Penhoat, Catherine Herve Du,Julia, Marc
-
-