Naturalproductman’s Blog

Hey, is that a natural product?!

Archive for the ‘Carbene’ Category

Dihydropyran access

Posted by naturalproductman on May 6, 2014

Carlos Saa and co-workers at Universidad de Santiago de Compostela have reported in ACIE on a reaction involving a ruthenium cascade followed by C-O formation to form dihydropyrans.

ruthenium
ACIE paper

Posted in Carbene, Cascade Reactions, Methodology, Ruthenium, Transition Metal | Leave a Comment »

Pyridines from 2H-azirines

Posted by naturalproductman on January 16, 2013

Cheol-Min Park and co-workers from Nanyang Technological University in Singapore have reported in ACIE on the synthesis of pyridines from 2H-azirines.

carbene

ACIE paper

Posted in Carbene, Cascade Reactions, Methodology, Rhodium, Transition Metal | Leave a Comment »

Juglomycin A synthesis

Posted by naturalproductman on November 12, 2012

Rodney Fernandes and co-workers from IIT Bombay have reported in JOC on a chromium carbene approach to access juglomycin.

chromium

JOC paper

Posted in Carbene, Cascade Reactions, Chromium, Methodology, Transition Metal | Leave a Comment »

Pyridine synthesis

Posted by naturalproductman on October 16, 2012

Cheol-Min Park and co-workers at Nanyang Technological University have reported in Chem Comm on a method for synthesis of pyridines through N-O bond cleavage using a carbenoid precursor.

pyridine

Chem Comm paper

Posted in Carbene, Cascade Reactions, Methodology | Leave a Comment »

Friedel-Crafts cascade

Posted by naturalproductman on April 4, 2012

Arun Ghosh and co-workers from Purdue have reported in Organic Letters on a Friedel-Crafts cascade to form a seven membered ring.
seven

OL paper

Posted in Carbene, Cascade Reactions, Friedel-Crafts, Methodology, Named Reactions, Seven-Membered Rings, Titanium, Transition Metal | Leave a Comment »

Loss of diazo group cascade

Posted by naturalproductman on March 29, 2012

Claude Spino and co-workers at Universite de Sherbrooke have reported in JACS on a [4+1] cascade.  A loss of a diazo group involved, hmm…reminds me of some of Dale Boger’s work.
diazo cascade

JACS paper

Posted in Carbene, Cascade Reactions, Methodology | Leave a Comment »

Loss of 2 x N2 to form carbenes

Posted by naturalproductman on February 29, 2012

Duncan Wardrop and co-worker from the University of Illinois in Chicago have reported in Organic Letters on an interesting approach to form a carbene by presumably forming a tetraazafulvene intermediate, which breaks down to the carbene by losing two molecules of nitrogen (ie:  N2).  At first I wondered how scary this reaction is because of the gain of entropy, but it looks pretty straight forward:  they just add DIC (diisopropylcarbodiimide) to the tetrazole and then load the reaction mixture directly on a column for purification.

Loss of N2

OL paper

Posted in Carbene, Cascade Reactions, Methodology | Leave a Comment »

Allenoates using NHCs

Posted by naturalproductman on February 21, 2012

Jianwei Sun and co-workers at Hong Kong University of Science and Technology have reported in Organic Letters on a carbene catalyzed formation of allenoates.

allenoates

OL paper

Posted in Allenes, Carbene, Cascade Reactions, Methodology | Leave a Comment »

From carbenoid to ring

Posted by naturalproductman on December 21, 2011

Jon Njardarson and co-workers at the University of Arizona have reported in Organic Letters on the synthesis of oxygen containing rings from diazocarbene.

ylide

OL paper

Posted in Carbene, Cascade Reactions, Copper, Methodology, Transition Metal | Leave a Comment »

Desymmetrizing a meso compound

Posted by naturalproductman on November 12, 2011

Pauline Chiu and co-workers from the University of Hong Kong have published in Tetrahedron Letters on a desymmetrization of a meso compound to form a five membered ring with modest ee (50% ee).

50%

TL paper

Posted in C2-Symmetric, Carbene, Copper, Desymmetrization, Methodology, Transition Metal | Leave a Comment »

 
Follow

Get every new post delivered to your Inbox.

Join 68 other followers