60753-91-5Relevant academic research and scientific papers
The influence of α-coordinating groups of aldehydes on E/Z-selectivity and the use of quaternary ammonium counter ions for enhanced E-selectivity in the Julia–Kocienski reaction
Rehman, Mintu,Surendran, Sravya,Siddavatam, Nagendra,Rajendar, Goreti
supporting information, p. 329 - 333 (2022/01/20)
Modified reaction conditions for improved E-selectivity of olefins in the Julia–Kocienski reaction of aldehydes having α-coordinating substituents are demonstrated. The chelating groups in aldehydes are expected to stabilize the syn-transition state with metal ions, whereas the weakly coordinating quaternary ammonium ions are devoid of all possible chelating interactions to enhance E-selectivity. A systematic investigation is presented to study the size of the neighbouring protecting groups of aldehydes and their chelation effect on E/Z-selectivity in the Julia–Kocienski reaction.
Catalytic Use of Elemental Gallium for Carbon-Carbon Bond Formation
Qin, Bo,Schneider, Uwe
supporting information, p. 13119 - 13122 (2016/10/25)
The first catalytic use of Ga(0) in organic synthesis has been developed by using a Ag(I) cocatalyst, crownether ligation, and ultrasonic activation. Ga(I)-catalyzed C-C bond formations between allyl or allenyl boronic esters and acetals, ketals, or aminals have proceeded in high yields with essentially complete regio- and chemoselectivity. NMR spectroscopic analyses have revealed novel transient Ga(I) catalytic species, formed in situ through partial oxidation of Ga(0) and B-Ga transmetalation, respectively. The possibility of asymmetric Ga(I) catalysis has been demonstrated.
Synthesis of Polysubstituted γ-Butenolides via a Radical Pathway: Cyclization of α-Bromo Aluminium Acetals and Comparison with the Cyclization of α-Bromoesters at High Temperature
Bénéteau, Romain,Despiau, Carole F.,Rouaud, Jean-Christophe,Boussonnière, Anne,Silvestre, Virginie,Lebreton, Jacques,Dénès, Fabrice
supporting information, p. 11378 - 11386 (2015/08/03)
Polysubstituted butenolides were obtained in good to high yields from α-bromoesters derived from propargyl alcohols by a one-pot reaction involving the radical cyclization of α-bromo aluminium acetals, followed by the oxidation of the resulting cyclic aluminium acetals in an Oppenauer-type process and migration of the exocyclic C-C bond into the α,β-position. Comparison with the direct cyclization of α-bromoesters at high temperature and under high dilution conditions is described. Deuterium-labelling experiments allowed us to uncover "invisible" 1,5-hydrogen atom transfers (1,5-HATs) that occur during these cyclization processes, together with the consequences of the latter in the epimerization of stereogenic centres. Compared to the classical approach, the cyclization of aluminium acetals proved to be highly chemoselective and its efficiency was illustrated by the short total syntheses of optically enriched γ-butenolides isolated from Plagiomnium undulatum and from Kyrtuhrix maculans.
Highly efficient triphenyl(3-sulfopropyl)phosphonium functionalized phosphotungstic acid on silica as a solid acid catalyst for selective mono-allylation of acetals
Kamble, Sumit B.,Shinde, Suhas H.,Rode, Chandrashekhar V.
, p. 4039 - 4047 (2015/08/03)
Silica supported phosphotungstic acid functionalized with triphenyl(3-sulfopropyl)phosphonium (PW-Si/TPSP) was developed as a solid acid catalyst for C-C bond formation via Hosomi-Sakurai allylation of acetals. Functionalization of PW as well as its bindi
Mesoporous aluminosilicate-catalyzed allylation of carbonyl compounds and acetals
Ito, Suguru,Hayashi, Akira,Komai, Hirotomo,Yamaguchi, Hitoshi,Kubota, Yoshihiro,Asami, Masatoshi
, p. 2081 - 2089 (2011/04/19)
A mesoporous aluminosilicate (Al-MCM-41) was found to be an effective heterogeneous catalyst for the reaction of both carbonyl compounds and acetals with allylsilanes to afford the corresponding homoallyl silyl ethers and homoallyl alkyl ethers, respectively. Both the mesoporous structure and the presence of aluminum moiety were indispensable for the high catalytic activity of Al-MCM-41. Moreover, Al-MCM-41 could catalyze the reaction of acetals chemoselectively in the presence of the corresponding carbonyl compounds. The solid acid catalyst Al-MCM-41 could be recovered easily by filtration and could be reused three times without a significant loss of catalytic activity.
Unusual carbon-carbon bond formations between allylboronates and acetals or ketals catalyzed by a peculiar indium(I) lewis acid
Schneider, Uwe,Dao, Hai T.,Kobayashi, Shu
supporting information; experimental part, p. 2488 - 2491 (2010/07/05)
InIOTf has been uncovered as an effective Lewis acid catalyst for unprecedented nucleophilic substitution of acetals or ketals with allylboronates. A transmetalative SN1 mechanism is proposed in which a single InI center acts as a dual catalyst to activate both reagents sequentially. Contrary to the classic γ-selectivity of allylsilanes (Hosomi-Sakurai reaction), this InI-catalyzed borono variant displays distinct α-selectivity. Substrate scope and functional group tolerance proved to be excellent.
Mesoporous aluminosilicate-catalyzed Sakurai allylation and Mukaiyama aldol reaction of acetals
Ito, Suguru,Hayashi, Akira,Komai, Hirotomo,Kubota, Yoshihiro,Asami, Masatoshi
experimental part, p. 4243 - 4245 (2010/09/07)
In the presence of a catalytic amount of mesoporous aluminosilicate (Al-MCM-41), both allyltrimethylsilane and silyl enol ether reacted with various acetals under mild reaction conditions to afford the corresponding homoallyl ethers and β-alkoxy ketones,
Trimethylsilyl trifluoromethanesulfonate catalyzed one-pot method for the conversion of aldehydes to homoallyl ethers in an ionic liquid
Anzalone, Peter W.,Mohan, Ram S.
, p. 2661 - 2663 (2007/10/03)
A mild method for the trimethylsilyl trifluoromethanesulfonate (TMSOTf) catalyzed one-pot synthesis of homoallyl ethers from aldehydes has been developed in the ionic liquid 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([bmim] [OTf]). The advanta
Niobium pentachloride-silver perchlorate as an efficient catalyst in the Friedel-Crafts acylation and Sakurai-Hosomi reaction of acetals
Arai, Shigeru,Sudo, Yukinori,Nishida, Atsushi
, p. 4639 - 4642 (2007/10/03)
Friedel-Crafts acylation catalyzed by niobium pentachloride with silver salt is described. Aromatic compounds with Ac2O or Bz2O were smoothly converted into the corresponding ketones in good to excellent yields. This system was also applied to the Sakurai-Hosomi reaction using acetals. The reaction proceeded quite rapidly to give the desired products in excellent yields.
Iron(III) chloride-catalyzed convenient one-pot synthesis of homoallyl benzyl ethers starting from aldehydes
Watahiki, Tsutomu,Akabane, Yusuke,Mori, Seiji,Oriyama, Takeshi
, p. 3045 - 3048 (2007/10/03)
(Matrix presented) Iron(III) chloride-catalyzed effective allylation reactions of acetals with allyltrimethylsilane proceeded smoothly in high to excellent yields. In addition, this method could be applied to the one-pot synthesis of homoallyl benzyl ethe
