An Enyne Cope Rearrangement Enables Polycycloalkane Synthesis from Readily Available Starting Materials
作者:Sarah K. Scott、Alexander J. Grenning
DOI:10.1002/anie.201703186
日期:2017.7.3
Knoevenagel adducts (cyclohexylidenemalononitriles) and two different propargyl electrophiles serve as carbon sources for assembling diverse 6/7/5 tricycloalkanes, a common terpenoid framework. The sequence involves three unique reactions: 1) deconjugative propargylation, 2) one‐pot enyne Cope rearrangement/deconjugative propargylation, and 3) an allenic Pauson–Khand reaction.
Methods and compositions for terpenoid tricycloalkane synthesis
申请人:University of Florida Research Foundation, Inc.
公开号:US10287239B1
公开(公告)日:2019-05-14
In one aspect, the disclosure relates to methods for preparation of intermediates useful for the preparation of terpenoid cores. In a further aspect, the disclosed methods pertain to the preparation of compounds comprising a terpenoid core or scaffold, such as 6/7/5 tricycloalkanes. The disclosed methods utilize abundant starting materials and simple reaction sequences that can be used to tunably and scalably assemble common terpenoid cores. In various aspects, the present disclosure pertains to compounds prepared using the disclosed methods. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.
[EN] METHODS AND COMPOSITIONS FOR TERPENOID SYNTHESIS<br/>[FR] PROCÉDÉS ET COMPOSITIONS POUR LA SYNTHÈSE DE TERPÉNOÏDES
申请人:UNIV FLORIDA
公开号:WO2018053322A1
公开(公告)日:2018-03-22
In one aspect, the disclosure relates to methods for preparation of terpene and terpene-like molecules. In a further aspect, the disclosure relates to the products of the disclosed methods, i.e., terpene and terpene-like molecules prepared using the disclosed methods. Intermediates for the synthesis of a wide variety of terpenoids are γ-allyl Knoevenagel adducts or quasi γ-allyl Knoevenagel adducts are disclosed. In various aspects, methods of preparing terpenoids through these intermediates are disclosed. The methods can comprise α-alkylation of an allylic electrophile followed by ring-closure metathesis to a polycyclic terpenoid structure. In a further aspect, the disclosure pertains to terpenoid frameworks, and compounds prepared via disclosed oxidation and substitution reactions on the disclosed terpenoid frameworks. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.
Transient [3,3] Cope rearrangement of 3,3-dicyano-1,5-dienes: computational analysis and 2-step synthesis of arylcycloheptanes
作者:Ehsan Fereyduni、Jacob N. Sanders、Gabriel Gonzalez、K. N. Houk、Alexander J. Grenning
DOI:10.1039/c8sc03057j
日期:——
reported. The two-step route from Knoevenagel adducts and allylic electrophiles is made possible through the design of a Coperearrangement that utilizes a “traceless” activating group to promote an otherwise thermodynamically unfavorable transformation. Experimentally, the [3,3] rearrangement occurrs transiently at room temperature with a computed barrier of 19.5 kcal mol−1, which ultimately allows for three-component
Promoting Thermodynamically Unfavorable [3,3] Rearrangements by Chemoselective Reduction
作者:Peter Vertesaljai、Roberto Serrano、Michael D. Mannchen、Matthew Williams、Evgeniya Semenova、Alexander J. Grenning
DOI:10.1021/acs.orglett.9b02057
日期:2019.7.19
Herein described is a strategy for promoting thermodynamically unfavorable [3,3] Cope rearrangements. 3,3-Dicyano-1,5-dienes that are resistant to the thermal rearrangement can be promoted under reductive conditions. The reduced Cope products are versatile, bifunctional building blocks.