94340-22-4Relevant academic research and scientific papers
Bi(cyclopentyl)diol-Derived Boronates in Highly Enantioselective Chiral Phosphoric Acid-Catalyzed Allylation, Propargylation, and Crotylation of Aldehydes
Yuan, Jinping,Jain, Pankaj,Antilla, Jon C.
, p. 12988 - 13003 (2020/11/23)
In this study, we disclose the catalytic addition of bi(cyclopentyl)diol-derived boronates to aldehydes promoted by chiral phosphoric acids, allowing for the formation of enantioenriched homoallylic, propargylic, and crotylic alcohols (up to >99% enantiom
Design and synthesis of new alkyl-based chiral phosphoric acid catalysts
Tang, Xiaoxue,He, Hualing,Fang, Xiantao,Chang, Zexu,Antilla, Jon C.
supporting information, p. 592 - 602 (2019/06/24)
Using chiral BINOL-derived phosphoric acids (PA's) to activate substrates for enhanced reactivity is now regarded as a powerful strategy to control enantioselectivity in asymmetric synthesis. Generally, most substituents at the 3,3′-positions of BINOL PA'
Enantioselective 1,2-Anionotropic Rearrangement of Acylsilane through a Bisguanidinium Silicate Ion Pair
Cao, Weidi,Tan, Davin,Lee, Richmond,Tan, Choon-Hong
supporting information, p. 1952 - 1955 (2018/02/17)
Highly enantioselective bisguanidinium-catalyzed tandem rearrangements of acylsilanes are reported. The acylsilanes were activated via an addition of fluoride on the silicon to form a penta-coordinate anionic silicate intermediate. The silicate then underwent alkyl or aryl group migration from the silicon atom to the neighboring carbonyl carbon atom (1,2-anionotropic rearrangement), followed by [1,2]-Brook rearrangement to provide the secondary alcohols in high yields with excellent enantioselectivities (up to 95% ee). The isolation of an α-silylcarbinol intermediate as well as DFT calculations revealed that the 1,2-anionotropic rearrangement occurred via a bisguanidinium silicate ion pair, which is the stereodetermining step. The chiral center formed is then retained without inversion through the subsequent [1,2]-Brook rearrangement. Crotyl acylsilanes were smoothly transformed into homoallylic linear crotyl alcohols with retention of E/Z geometry, and no branched alcohols were detected. This clearly suggested that the 1,2-anionotropic rearrangement occurred through a three-membered instead of a five-membered transition state.
Asymmetric Allylation of Carbonyl Compounds Catalyzed by a Chiral Phosphine–Silver Complex
Yanagisawa, Akira,Yang, Nan,Bamba, Kentaro
supporting information, p. 6614 - 6618 (2017/12/15)
A catalytic, asymmetric allylation reaction of aldehydes or ketones with allyltrimethoxysilane was achieved by using a BINAP·AgBF4 [BINAP = 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl] complex as the chiral precatalyst and triethylamine as the
Enantioselective Allyl-, and Allenylboration of Aldehydes Catalyzed by Chiral Hydroxyl Carboxylic Acid
Ota, Yuya,Kawato, Yuji,Egami, Hiromichi,Hamashima, Yoshitaka
supporting information, p. 976 - 980 (2017/05/05)
Asymmetric allylboration of aldehydes with allylboronic acid pinacol ester catalyzed by chiral hydroxyl carboxylic acid is described. This reaction provides synthetically useful homoallyl alcohols in high yield with good to high enantioselectivity. The pr
A chiral bipyridyl alcohol for catalytic enantioselective Nozaki-Hiyama-Kishi allylation of aldehydes and ketones
Chen, Rui-Yu,Dhondge, Attrimuni P.,Lee, Gene-Hsian,Chen, Chinpiao
supporting information, p. 961 - 966 (2015/03/30)
A class of bipyridyl alcohol ligands has been developed. A catalyst synthesized using a chromium(II)-ligand promotes the enantioselective Nozaki-Hiyama-Kishi (NHK) allylation of aldehydes and ketones with allylic halides. The allylation of various aromati
Br?nsted acid-catalyzed asymmetric allylation and propargylation of aldehydes
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Page/Page column 8; 21; 22, (2013/08/28)
A method synthesizing homoallylic or homopropargylic alcohols was developed to react aldehydes with allyl boronates, such as allylboronic acid pinacol ester, or allenylborates in the presence of a catalytic amount of a chiral binaphthyl-derived chiral pho
Protecting-group-free diastereoselective C-C coupling of 1,3-glycols and allyl acetate through site-selective primary alcohol dehydrogenation
Dechert-Schmitt, Anne-Marie R.,Schmitt, Daniel C.,Krische, Michael J.
supporting information, p. 3195 - 3198 (2013/04/24)
Safe from protection! A pronounced kinetic preference for primary alcohol dehydrogenation enables the site-selective iridium catalyzed C-C coupling of polyols with allyl acetate in the absence of protecting groups, premetallated reagents, chiral auxiliaries, and discrete alcohol-to-aldehyde oxidation.
Conformationally rigid chiral pyridine N-oxides as organocatalyst: Asymmetric allylation of aldehydes
Gnanamani, Elumalai,Someshwar, Nagamalla,Ramanathan, Chinnasamy Ramaraj
supporting information, p. 2101 - 2106 (2012/11/07)
A pyridine unit with a conformationally rigid chiral backbone has been designed and synthesized in an enantiomerically pure form to utilize in the Lewis base-catalyzed Sakurai-Hosomi-Denmark-type allylation reaction. The chiral pyridine N-oxide in 1:1 mix
A pineno-salen type catalyst for the enantioselective Nozaki-Hiyama-Kishi reaction
Dhondge, Attrimuni P.,Shaikh, Ajam C.,Chen, Chinpiao
, p. 723 - 733 (2012/08/29)
A new class of pineno-salen type ligands 10, 11, 17, 20, 23, and 24 has been developed. The catalyst formed from chromium(II)-10 promotes the enantioselective Nozaki-Hiyama-Kishi allylation of alkyl and aryl aldehydes using allyl bromide. Notably, the asymmetric addition of vinyl halide to benzaldehyde was achieved with 24% ee.
