6683-49-4Relevant articles and documents
Palladium-Catalyzed Electrochemical Allylic Alkylation between Alkyl and Allylic Halides in Aqueous Solution
Lai, Yin-Long,Huang, Jing-Mei
supporting information, p. 2022 - 2025 (2017/04/28)
A new route for the direct cross-coupling of alkyl and allylic halides using electrochemical technique has been developed in aqueous media under air. Catalyzed by Pd(OAc)2, the Zn-mediated allylic alkylations proceed smoothly between a full range of alkyl halides (primary, secondary, and tertiary) and substituted allylic halides. Protection-deprotection of acidic hydrogen in the substrates is avoided.
Palladium-catalyzed desulfinylative C-C allylation of Grignard reagents and enolates using allylsulfonyl chlorides and esters
Rao Volla, Chandra M.,Dubbaka, Srinivas Reddy,Vogel, Pierre
experimental part, p. 504 - 511 (2009/04/07)
2-Methylprop-2-ene-, prop-2-ene-, 1-methylprop-2-ene-, and (E)-but-2-enesulfonyl chlorides have been used as electrophilic partners in desulfinylative palladium-catalyzed C-C coupling with Grignard reagents and sodium salts of dimethyl malonate and methyl
Ligandless iron-catalyzed desulfinylative C-C allylation reactions using Grignard reagents and alk-2-enesulfonyl chlorides
Volla, Chandra M. R.,Markovic, Dean,Dubbaka, Srinivas Reddy,Vogel, Pierre
experimental part, p. 6281 - 6288 (2011/02/28)
Alk-2-enesulfonyl chlorides 1-4 were synthesized by the BCl3-promoted ene reaction of alkenes with SO2. These sulfonyl chlorides were then used as electrophilic partners in iron-catalyzed desulfinylative cross-coupling reactions with different Grignard reagents (aromatic, aliphatic, and heteroaromatic). The reaction can be catalyzed with even 2 mol-% of the simple iron salt Fe(acac)3. The regioselectivity of these allylations was studied by using sulfonyl chlorides 3 and 4 with aryl Grignard reagents. The scope of these allylations was further extended by the coupling of ester-substituted alk-2-enesulfonyl chloride 10 with aromatic Grignard reagents. Symmetrical products were synthesized by double C-C allylation with the use of 2-methylidenepropane-1,3-disulfonyl chloride (12). Wiley-VCH Verlag GmbH & Co. KGaA.
Preparation of 2-trimethylsilylmethyl-1-alkene; cross-coupling and protodesilylation sequence from 1,1-dibromo-1-alkene
Uenishi, Jun'ichi,Iwamoto, Takuya,Ohmi, Masashi
, p. 1237 - 1240 (2007/10/03)
A new method for the preparation of exomethylene type allylsilane is described. Selective mono-protodesilylation of 1-trimethylsilyl-2-trimethylsilylmethyl-2-alkenes 2 with PPTS afforded 2-trimethylsilylmethyl-1-alkenes 4 in excellent yields. Since the resulting allylsilanes 4 possess an exomethylene unit, the reactions of 4 with carbonyl compounds in the presence of Lewis acids gave the corresponding product 7 having an exomethylene unit in excellent yields.
Reactions of 1,1-bis(silylmethyl)-1-alkene with N-halosuccinimide and ozone
Uenishi, Jun'ichi,Tanaka, Yusuke,Ohmi, Masashi,Shimomura, Hotsumi,Kawai, Nobuyuki
, p. 595 - 602 (2007/10/03)
Electrophilic reactions of 3-phenyl-1,1-bis(trimethylsilymethyl)-1-propene (1) and 1,1-bis[dimethyl(phenyl)silylmethyl]-3-phenyl-1-propene (4) are described. Protodesilylation of 1 with PPTS gave 2-substituted allylsilane (2) in excellent yield. Halogenat
Chromium(III) catalyzed synthesis of allenes from propargyl derivatives via a carbometalation-elimination sequence
Molander, Gary A.,Sommers, Erin M.
, p. 2345 - 2349 (2007/10/03)
The syn-carbometalation/syn-elimination of propargyl substrates to form allenes has been achieved using cationic chromium(III) catalysts activated by alkylaluminums. The mechanism and scope of this transformation are presented.
Ru(III)-Catalyzed Cyclization of Arene-Alkene Substrates via Intramolecular Electrophilic Hydroarylation
Youn, So Won,Pastine, Stefan J.,Sames, Dalibor
, p. 581 - 584 (2007/10/03)
(Matrix presented) We herein report that RuCl3/AgOTf has proven to be a hydroarylation catalyst with an efficiency and scope superior to previously known methods. This catalyst demonstrated consistent performance with arene-ene substrates of diverse structural features, providing good to excellent yields of cyclization products (chromanes, tetralins, terpenoids, dihydrocoumarins).
Surface-Mediated Reactions. 6. Effects of Silica Gel and Alumina on Acid-Catalyzed Reactions
Kropp, Paul J.,Breton, Gary W.,Craig, Stephen L.,Crawford, Scott D.,Durland, William F.,et al.
, p. 4146 - 4152 (2007/10/02)
Absorption of a variety of acids to chromatographic silica gel results in substantial enhancement of their catalytic activity-affording easily prepared, environmentally benign heterogeneous acids that are highly effective in mediating a number of processes.This was shown for the isomerization of allene 1 and dimerization of the corresponding 1,3-diene 2; cyclization of (R)-citronellal (5), the related diester 10, and 1,5-cyclooctadiene (15); Rupe rearrangement of alkynol 18; and Friedel-Crafts cyclodehydration of alcohols 21.By contrast, commercially available Nafion-H was significantly less effective as a heterogeneous acid catalyst.Chromatographic alumina displayed enigmatic behavior, showing enhanced acidity on the adsorption of HCl but little or no acidity on the adsorption of a variety of other types of acid.The results are discussed in terms of the surface structures of silica gel and alumina.
Substituent Effects on the Intramolecular Photochemical Reactions of Phenyl-Ethenyl Non-conjugated Bichromophoric Systems
Ellis-Davies, Graham C. R.,Gilbert, Andrew,Heath, Peter,Lane, Jon C.,Warrington, John V.,Westover, David L.
, p. 1833 - 1842 (2007/10/02)
The effects of substitution on the photochemistry of phenyl-ethenyl bichromophoric systems are reported.Methyl substitution at the 2-, 3-, 5-, and 1,1,2-positions in the pentene moiety of 5-phenylpent-1-ene reduces both reaction efficiency and selectivity but in contrast to intramolecular analogues the photoreaction of 3-phenethylcyclohexene is comparable with that of the corresponding cyclopentene.Incorporation of ester units in the connecting unit between the chromophores or on the ethene inhibits intramolecular cyclisation as does the presence of para OMe, CN, or COMe groups in 5-phenylpent-1-ene.In contrast reaction selectivity and efficiency are greatly promoted by ortho Me or OMe groups and the products reflect exlusive 1,3-cycloaddition.The presence of a para Me group in 5-phenylpent-1-ene leads to specific 2,6-intramolecular cyclisation but the reaction of the meta-Me derivative leads to four products derived from 1,3- and 1,5-intramolecular cycloaddition.The observations are discussed in terms of mechanisms of arene-ethene photoreactions and preferred conformations of the bichromophores.
