Copper-Catalyzed Skeletal Rearrangement of O-Propargylic Aryloximes into Four-Membered Cyclic Nitrones - Chirality Transfer and Mechanistic Insight
摘要:
Copper-catalyzed skeletal rearrangement of O-propargylic aryloximes (E)-1 were carried out to afford the corresponding four-membered cyclic nitrones 2 in good to excellent yields. The optimal reactions conditions of the highly regioselective reactions involved the use of [CuCl(cod)](2) in acetonitrile at 70 degrees C. In the case of (Z)-1, however, the reaction proceeded in the absence of the copper catalysts to afford the identical compound 2 in good yields. Furthermore, the reactions were also carried out using chiral substrates (R)-1 in the presence of Cu catalysts to afford (R)-2 with good levels of chirality transfer.
One-Pot Assembly of 3-Hydroxycarbazoles via Uninterrupted Propargylation/Hydroxylative Benzannulation Reactions
作者:Chada Raji Reddy、Muppidi Subbarao、Puppala Sathish、Dattahari H. Kolgave、Ramachandra Reddy Donthiri
DOI:10.1021/acs.orglett.9b04472
日期:2020.1.17
A novel strategy for the synthesis of 3-hydroxycarbazoles involving the consecutive propargylation/palladium-catalyzed hydroxylative benzannulation of indole-2-carbonyls with propargylic alcohols has been exploited. This one-pot procedure leads to a wide range of substituted 3-hydroxycarbazoles in high yield with a broad substrate scope. The method was further extended to access furano-carbazole derivatives
METHOD FOR PREPARING PROPARGYLIC ALCOHOL CATALYZED BY 2-MORPHOLINOISOBORNANE-10-THIOL
申请人:UANG Biing-Jiun
公开号:US20110295042A1
公开(公告)日:2011-12-01
A method for preparing a propargylic alcohol catalyzed by 2-morpholinoisobornane-10-thiol (MITH) is disclosed, which includes reacting R
1
CHO with R
2
CCH in the presence of R
3
ZnR
4
and MITH, wherein each of R
1
, R
2
, R
3
, and R
4
, independently, is optionally substituted alkyl, alkenyl, cycloalkyl, cycloalkenyl, alkylsilyl, heterocycloalkyl, heterocycloalkenyl, aryl, aryloxy, or heteroaryl. The method can give enantioenriched propargylic alcohols with good enantioselective at low loading of MITH.
Ynones Merge Activation/Conjugate Addition of Chalcogenoborates ArE-Bpin (E=Se, S)
作者:Marc G. Civit、Xavier Sanz、Christopher M. Vogels、Carles Bo、Stephen A. Westcott、Elena Fernández
DOI:10.1002/adsc.201500650
日期:2015.10.12
The “pull–push” effect of the Bpin moiety in ArE-Bpin reagents (E=Se, S) is demonstrated by the Lewis acid interaction with the carbonyl group of ynones and the concomitant delivery of ArSe or ArS to the electron-deficient alkyne with impressive stereoselectivity. The two component reactivity is carried out in methanol to generate (Z)-β-(arylseleno)-α,β-unsaturated ketones and (Z)-β-(arylsulfuro)-α
Copper-Catalyzed Direct Coupling of Unprotected Propargylic Alcohols with P(O)H Compounds: Access to Allenylphosphoryl Compounds under Ligand- and Base-Free Conditions
The first facile and efficient copper-catalyzeddirect C–P cross-coupling of unprotected propargylic alcohols with P(O)H compounds has been developed, providing a general, one-step approach to construct valuable allenylphosphoryl frameworks with operational simplicity and high step- and atom-economy under ligand-, base-, and additive-free conditions.
first facile and efficient Zn(OTf)2-catalyzed direct coupling of unprotected propargylic alcohols with arylphosphine oxides has been developed, affording a general, one-step approach to access structurally diverse γ-ketophosphine oxides via sequential Meyer–Schuster rearrangement/phospha-Michael reaction along with new C(sp3)—P and C═Obondformations, operational simplicity, and complete atom economy