58927-85-8Relevant academic research and scientific papers
Selective Isomerization of Terminal Alkenes to (Z)-2-Alkenes Catalyzed by an Air-Stable Molybdenum(0) Complex
Becica, Joseph,Glaze, Owen D.,Wozniak, Derek I.,Dobereiner, Graham E.
, p. 482 - 490 (2018/02/17)
Positional and stereochemical selectivity in the isomerization of terminal alkenes to internal alkenes is observed using the cis-Mo(CO)4(PPh3)2 precatalyst. A p-toluenesulfonic acid (TsOH) cocatalyst is essential for catalyst activity. Various functionalized terminal alkenes have been converted to the corresponding 2-alkenes, generally favoring the Z isomer with selectivity as high as 8:1 Z:E at high conversion. Interrogation of the catalyst initiation mechanism by 31P NMR reveals that cis-Mo(CO)4(PPh3)2 reacts with TsOH at elevated temperatures to yield a phosphine-ligated Mo hydride (MoH) species. Catalysis may proceed via 2,1-insertion of a terminal alkene into a MoH group and stereoselective β-hydride elimination to yield the (Z)-2-alkene.
Chiral a-substituted allylboronates in a one-pot three-component asymmetric allylic alkylation/carbonyl allylation reaction sequence -Applications to the syntheses of (+)-(3R,5R)-3-hydroxy-5-decanolide and (-)-massoialactone
Carosi, Lisa,Hall, Dennis G.
experimental part, p. 650 - 661 (2009/10/30)
The use of different organomagnesium reagents in the copper-catalyzed allylic alkylation of 3-chloropropenyl with chiral phosphoramidite ligands produces the desired a-substituted allylic boronate reagents in high and with modest to high enantioselectivities (up to 96% ee). The size of the incoming alkyl substituent the organomagnesium reagent was found to impact the yield and selectivity of the allylic alkylation. A one-pot for the preparation of these chiral allylic boronates followed by a Lewis acid (BF3) catalyzed addition to aldehydes the desired allylboration products, homoallylic secondary alcohols, in good yields and very high diastereoselectivity.three-component reaction methodology was applied to the syntheses of two lactone-containing natural , (-)-massoialactone and (+)-(3R,5R)-3-hydroxy-5-decanolide. The key step of these syntheses involved the pot enantioselective copper-catalyzed allylic alkylation/allylboration reaction with a benzylic aldehyde, and the desired product in 87% yield, 92% e,and high E/Z selectivity in a ratio of 22:1. Remarkably, the alkylation step of this sequential reaction was performed with a low catalyst loading of 2 mol% on a scale >15 mmol that can provide multiple grams of the three-component product.
α-Regioselective and Stereospecific Addition of Allylic Tins to Aldehydes via Photoinduced Electron Transfer
Takuwa, Akio,Shiigi, Junji,Nishigaichi, Yutaka
, p. 3457 - 3460 (2007/10/02)
(E)- and (Z)-Allylic tributyltins add to aromatic aldehydes to afford regioreversed α-adduct predominantly with almost complete retention of the stereochemistry of the allylic groups under photochemical conditions.The photoinduced single electron transfer mechanism is proposed.
One-Pot Synthesis of Substituted Homoallylic Alcohols (3-Alkenols) and 1-Deuterio-3-alkenols; II. Extension to Ketone Enolates
Barluenga, Jose,Alvarez, Flora,Concellon, Jose M.,Bernad, Pablo,Yus, Miguel
, p. 318 - 320 (2007/10/02)
The reaction of different lithium ketone enolates with α-chloro carbonyl compounds followed by in situ reduction with lithium aluminium hydride or deuteride and final lithiation with lithium powder leads to the corresponding homoallylic or 1-deuterio homoallylic alcohols in a regioselective manner.
Stereoselective Synthesis of Alcohols, XXII. E/Z-Selectivity on Addition of α-Substituted Allylboronates to Aldehydes
Hoffmann, Reinhard W.,Landmann, Bernd
, p. 1039 - 1053 (2007/10/02)
α-Heterosubstituted allylboronates 7 are prepared.Addition of 7 to aldehydes results in E/Z-isomeric homoallyl alcohols 13 and 14.The reasons for the predominant formation of the Z-isomer 14 are discussed.The Z-bromo olefins 16 and 20 obtained in this way serve as starting point for chain extension or formation of δ-lactones 21.
Selective Synthesis of either Branched or Linear Homoallyl Alcohols via the Reaction of Aldehydes with the Allylic Borane-Selenium System
Yamamoto, Yoshinori,Saito, Yoshikazu,Maruyama, Kazuhiro
, p. 5408 - 5409 (2007/10/02)
Either branched (2) or linear (3) homoallyl alcohols can be prepared independently by choosing the reaction conditions through the reaction of (phenylselenyl)allyl carbanion with trialkylboranes.
Z-SELECTIVE FORMATION OF SUBSTITUTED HOMOALLYL ALCOHOLS
Hoffmann, Reinhard W.,Landmann, Bernd
, p. 3209 - 3212 (2007/10/02)
The α-substituted allylboronates 4 add to aldehydes giving with high Z-preference the homoallyl alcohols 1.The Z-vinyl bromides obtained were further converted into δ-lactones.
