Results 51 to 60 of about 337 (160)

Regio- and Diastereoselective [3 + 2]-Spiroannulation of Benzoxazines with Chalcones: A Rh(III)-Catalyzed Redox-Neutral Approach to α‑Aroyl Spiro-Indanamines

We report an atom-economic Rh­(III)-catalyzed [3 + 2]-spiroannulation reaction between cyclic ketimines and α,β-unsaturated carbonyl compounds, allowing the synthesis of novel spirocycles with concomitant generation of three stereogenic centers in one ...
Imtiaj Mondal (13039943), Koushik Naskar (7510592), Indubhusan Deb (1844146), Shantonu Roy (13039940), Writhabrata Sarkar (6387272), Sudip Karmakar (9705129), Aniket Mishra (2886182)   +6 more
core   +2 more sources

Synergistic Sc(III)/Au(I)-Catalyzed Dearomative Spiroannulation of 2‑(Ethynyl)aryl Cyclopropanes with 2‑Aryl Indoles

The diastereoselective assembly of spiroindolenines via a synergistic scandium/gold-catalyzed dearomative spiroannulation is herein described. This protocol offers access to a wide variety of spiroindolenine derivatives in 86% average yield with moderate
Yanmin Huang (1515796), Ru-Fang Meng (14141341), Jun-An Xiao (1478809), Hai Peng (426694), Huan Zhang (220065), Wei Su (89824), Chenxiang Lin (1478593)   +6 more
core   +1 more source

Synthetic approaches to komarovispiranes. Enantiospecific synthesis of bicyclo[3.3.0]octanespiro[3.1']cyclohexanes

, 2007
A ring-closing metathesis based spiroannulation of cyclopentane and cyclohexanes at the C-3 carbon atom of a bicyclo[3.3.0]octane, as a model study directed towards the enantiospecific synthesis of the novel diterpenes komarovispiranes, is ...
Beeraiah, B., Srikrishna, A.
core   +2 more sources

2-(Trimethylsilyloxy)furan as a dianion equivalent: a two-step synthesis of functionalized spirocyclic butenolides.

, 2006
[reaction: see text] The use of 2-(trimethylsilyloxy)furan derivatives as dianion equivalents leads to a general and connective spiroannulation protocol for the efficient preparation of spirocyclic ...
Maulide, Nuno, Nuno Maulide, Marko, Istvan, Istvan E. Marko   +3 more
core   +1 more source

2-(Trimethylsilyloxy)furan as a Dianion Equivalent:  A Two-Step Synthesis of Functionalized Spirocyclic Butenolides

, 2016
The use of 2-(trimethylsilyloxy)furan derivatives as dianion equivalents leads to a general and connective spiroannulation protocol for the efficient preparation of spirocyclic ...
István E. Markó (2476828), Nuno Maulide (1393489)   +1 more
core   +1 more source

Connective synthesis of spirovetivanes: Total synthesis of (+/-)-agarospirol, (+/-)-hinesol and (+/-)-alpha-vetispirene

, 2004
A concise, connective synthesis of naturally occurring spirovetivanes 1 and 3, in racemic form, is presented. This novel approach involves the efficient assembly of the advanced intermediate 12 through a unique spiroannulation ...
Maulide, Nuno, Vanherck, JC., Nuno Maulide, Jean‐Christophe Vanherck, István E. Markó, Marko, Istvan   +5 more
core   +1 more source

Enantioselective palladium-catalyzed C(sp²)-C(sp²) σ bond activation of cyclopropenones by merging desymmetrization and (3 + 2) spiroannulation with cyclic 1,3-diketones. [PDF]

Chem Sci, 2021
Zhou HQ, Gu XW, Zhou XH, Li L, Ye F, Yin GW, Xu Z, Xu LW.   +7 more
europepmc   +1 more source

An Expedient Route to a Potent Gastrin/CCK-B Receptor Antagonist (+)-AG-041R

, 2016
An enantiocontrolled synthesis of (+)-AG-041R (1), a potent gastrin/CCK-B receptor antagonist, has been achieved employing a chiral rhodium(II)-catalyzed, oxidative intramolecular aza-spiroannulation as the key ...
Yoshiharu Iwabuchi (1389561), Masatoshi Shibuya (1368624), Naoki Kanoh (1389567), Shigeki Sato (2346835)   +3 more
core   +1 more source

A rapid access to spiroaminoketal framework.

, 2005
A convergent and stereoselective synthesis of 1-oxa-7-azaspiro[5.5]undecane is described. This functional new spiroheterocycle is readily available from acetone ?n?-dimethylhydrazone via a double alkylation and subsequent spiroannulation ...
Sinibaldi, Marie-Eve, Tursun, Ahmatjan, Martin, Anne-Sophie, Canet, Isabelle, Aboab, Bettina   +4 more
core   +1 more source

Rapid syntheses of N-fused heterocycles via acyl-transfer in heteroaryl ketones. [PDF]

Nat Commun, 2022
Ye D, Lu H, He Y, Zheng Z, Wu J, Wei H.
europepmc   +1 more source