scholarly journals A Relay Strategy Actuates Pre-Existing Trisubstituted Olefins in Monoterpenoids for Cross-Metathesis with Trisubstituted Alkenes

2020 ◽  
Vol 85 (7) ◽  
pp. 4906-4917 ◽  
Author(s):  
Karim A. Bahou ◽  
D. Christopher Braddock ◽  
Adam G. Meyer ◽  
G. Paul Savage ◽  
Zhensheng Shi ◽  
...  
Keyword(s):  
Cross Metathesis ◽  
Trisubstituted Olefins ◽  
Trisubstituted Alkenes

scholarly journals A Relay Strategy Actuates Pre-Existing Trisubstituted Olefins in Monoterpenoids to Form New Trisubstituted Olefins by Cross Metathesis

2019 ◽  
Author(s):  
Karim Bahou ◽  
D. Christopher Braddock ◽  
Adam G. Meyer ◽  
G. Paul Savage ◽  
Zhensheng Shi ◽  
...  
Keyword(s):  
Geometrical Isomer ◽  
Successful Implementation ◽  
Enantiomerically Pure ◽  
Cross Metathesis ◽  
Trisubstituted Olefins ◽  
The Cross ◽  
Trisubstituted Alkenes

<b><u>Abstract:</u></b> A retrosynthetic disconnection-reconnection analysis of epoxypolyenes – substrates that can undergo cyclization to podocarpane-type tricycles – reveals relay-actuated Δ<sup>6,7</sup>-functionalized monoterpenoid alcohols for ruthenium benzylidene catalyzed olefin cross metathesis with homoprenyl benzenes. Successful implementation of this approach provided several epoxypolyenes as expected (<i>E</i>:<i>Z</i>, ca. 2-3:1). The method is further generalized for the cross metathesis of pre-existing trisubstituted olefins in other relay-actuated Δ<sup>6,7</sup>-functionalized monoterpenoid alcohols with various other trisubstituted alkenes to form new trisubstituted olefins. Epoxypolyene cyclization of an enantiomerically pure, but geometrically impure, epoxypolyene substrate provides an enantiomerically pure, trans-fused, podocarpane-type tricycle (from the <i>E</i>-geometrical isomer).<br>

A Relay Strategy Actuates Pre-Existing Trisubstituted Olefins in Monoterpenoids to Form New Trisubstituted Olefins by Cross Metathesis

2019 ◽  
Author(s):  
Karim Bahou ◽  
D. Christopher Braddock ◽  
Adam G. Meyer ◽  
G. Paul Savage ◽  
Zhensheng Shi ◽  
...  
Keyword(s):  
Geometrical Isomer ◽  
Successful Implementation ◽  
Enantiomerically Pure ◽  
Cross Metathesis ◽  
Trisubstituted Olefins ◽  
The Cross ◽  
Trisubstituted Alkenes

<b><u>Abstract:</u></b> A retrosynthetic disconnection-reconnection analysis of epoxypolyenes – substrates that can undergo cyclization to podocarpane-type tricycles – reveals relay-actuated Δ<sup>6,7</sup>-functionalized monoterpenoid alcohols for ruthenium benzylidene catalyzed olefin cross metathesis with homoprenyl benzenes. Successful implementation of this approach provided several epoxypolyenes as expected (<i>E</i>:<i>Z</i>, ca. 2-3:1). The method is further generalized for the cross metathesis of pre-existing trisubstituted olefins in other relay-actuated Δ<sup>6,7</sup>-functionalized monoterpenoid alcohols with various other trisubstituted alkenes to form new trisubstituted olefins. Epoxypolyene cyclization of an enantiomerically pure, but geometrically impure, epoxypolyene substrate provides an enantiomerically pure, trans-fused, podocarpane-type tricycle (from the <i>E</i>-geometrical isomer).<br>

Synthesis of Trisubstituted Alkenes via Olefin Cross-Metathesis

1999 ◽  
Vol 1 (11) ◽  
pp. 1751-1753 ◽  
Author(s):  
Arnab K. Chatterjee ◽  
Robert H. Grubbs
Keyword(s):  
Cross Metathesis ◽  
Trisubstituted Alkenes

An Atom-Economic and Stereospecific Access to Trisubstituted Olefins through Enyne Cross Metathesis Followed by 1,4-Hydrogenation

Synlett ◽  
2018 ◽  
Vol 29 (06) ◽  
pp. 785-792 ◽  
Author(s):  
Hans-Günther Schmalz ◽  
Friederike Ratsch
Keyword(s):  
Functional Group ◽  
Cross Metathesis ◽  
Broad Scope ◽  
Trisubstituted Olefins

The combination of intermolecular enyne cross metathesis and subsequent 1,4-hydrogenation opens a stereocontrolled and atom-economic access to trisubstituted olefins. By investigating different combinations of functionalized alkyne and alkene substrates, we found that the outcome (yield, E/Z ratio) of the Grubbs II-catalyzed enyne cross-metathesis step depends on the substrate’s structure, the amount of the alkene (used in excess), and the (optional) presence of ethylene. In any case, the 1,4-hydrogenation, catalyzed by 1,2-di­methoxybenzene-Cr(CO)3, proceeds stereospecifically to yield exclusively the E-products from both the E- and Z-1,3-diene intermediates obtained by metathesis. A rather broad scope and functional group compatibility of the method is demonstrated by means of 15 examples.

scholarly journals Diastereoselective synthesis of trisubstituted olefins using a silicon-tether ring-closing metathesis strategy

2020 ◽  
Vol 18 (12) ◽  
pp. 2297-2306
Author(s):  
Stéphane Wittmann ◽  
Alexander F. Tiniakos ◽  
Joëlle Prunet
Keyword(s):  
Diastereoselective Synthesis ◽  
Ring Closing Metathesis ◽  
Trisubstituted Olefins ◽  
Trisubstituted Alkenes

We report an efficient and diastereoselective synthesis of E- and Z-trisubstituted alkenes by a silicon-tether ring-closing metathesis strategy.

scholarly journals Synthesis of E- and Z-trisubstituted alkenes by catalytic cross-metathesis

Nature ◽  
2017 ◽  
Vol 552 (7685) ◽  
pp. 347-354 ◽  
Author(s):  
Thach T. Nguyen ◽  
Ming Joo Koh ◽  
Tyler J. Mann ◽  
Richard R. Schrock ◽  
Amir H. Hoveyda
Keyword(s):  
Cross Metathesis ◽  
Trisubstituted Alkenes

ChemInform Abstract: Synthesis of Trisubstituted Alkenes via Olefin Cross-Metathesis.

ChemInform ◽  
2010 ◽  
Vol 31 (8) ◽  
pp. no-no
Author(s):  
Arnab K. Chatterjee ◽  
Robert H. Grubbs
Keyword(s):  
Cross Metathesis ◽  
Trisubstituted Alkenes

Synthesis of Symmetrical Trisubstituted Olefins by Cross Metathesis

2002 ◽  
Vol 4 (11) ◽  
pp. 1939-1942 ◽  
Author(s):  
Arnab K. Chatterjee ◽  
Daniel P. Sanders ◽  
Robert H. Grubbs
Keyword(s):  
Cross Metathesis ◽  
Trisubstituted Olefins

ChemInform Abstract: Synthesis of Symmetrical Trisubstituted Olefins by Cross Metathesis.

ChemInform ◽  
2010 ◽  
Vol 33 (42) ◽  
pp. no-no
Author(s):  
Arnab K. Chatterjee ◽  
Daniel P. Sanders ◽  
Robert H. Grubbs
Keyword(s):  
Cross Metathesis ◽  
Trisubstituted Olefins

scholarly journals Relay Cross Metathesis for the Iterative Ascent of the Terpenoids

2019 ◽  
Author(s):  
Karim Bahou ◽  
D. Christopher Braddock ◽  
Adam G. Meyer ◽  
G. Paul Savage ◽  
Zhensheng Shi
Keyword(s):  
Natural Products ◽  
Functional Group ◽  
Building Blocks ◽  
Design And Implementation ◽  
Cross Metathesis ◽  
Naturally Occurring ◽  
Trisubstituted Olefins

<div>We report the design and implementation of a relay cross</div><div>metathesis (ReXM) reaction for the ascent of the terpenoids in an iterative protocol. The method features the reaction of naturally occurring terpenoid building blocks – with preexisting trisubstituted olefins – which combine to construct a new trisubstituted olefin resulting in a five-carbon unit homologation. Subsequent functional group manipulation allows for the method to be repeated in an</div><div>iterative fashion. The method is used for the synthesis of a diterpenebenzoate macrolide of biogenetic relevance to the bromophycolide family of natural products.</div>

Sign in / Sign up

Export Citation Format

Share Document