Naturalproductman’s Blog

Hey, is that a natural product?!

Archive for January, 2016

Chiral phosphoric acid for allenamides with ketones

Posted by naturalproductman on January 29, 2016

Dean Toste and colleague have reported in Chemical Science on the use of a chiral phosphoric acid catalyst to react allenamides with ketones. I guess the papers published in Chemical Science in 2015 and 2016 are all open access.

 

Chemical Science paper

Advertisements

Posted in Allenes, Methodology, Organocatalytic | Leave a Comment »

Jungermannenones B and C synthesis

Posted by naturalproductman on January 29, 2016

Xiaoguang Lei and co-workers from Peking University have reported in ACIE on the synthesis of jungermannenones B and C.

 

ACIE paper

Posted in Cascade Reactions, Methodology, Radical Chemistry, Total Synthesis | Leave a Comment »

3 Diels-Alder reactions in 1 go

Posted by naturalproductman on January 29, 2016

Michael Sherburn and co-workers from the Australian National University reported in JOC on a Diels-Alder cascade sequence.

DIELS ALDER CASCADE 01.29.2016.gif

JOC paper

 

Here’s an interesting related ACIE paper by the same group.

Posted in Cascade Reactions, Diels-Alder, Methodology, Named Reactions | Leave a Comment »

2 Reagents, 2 mechanisms, same product

Posted by naturalproductman on January 28, 2016

Srinivasan Chandrasekaran and colleague at the Indian Institute of Science have reported in Tetrahedron on a mechanistically interesting transformation involving a geminal aminooxygenation of a vinyl arene. Two different reaction conditions were identified: one with m-CPBA, the other with a hypervalent iodine reagent. The former underwent a deuterium shift on the gem-dideuterated-styrene starting material and the latter does not.

01.28.2016 naturalproductman.gif

Tetrahedron paper

Posted in Cascade Reactions, Hypervalent Iodine, Mechanistic, Methodology | Leave a Comment »

Expect the unexpected – allylic alcohols from epoxides

Posted by naturalproductman on January 27, 2016

Margaret Brimble and co-workers from the University of Auckland have reported in Organic Letters on a cobalt-catalyzed conversion of an epoxide to an allylic alcohol using the Corey-Chaykovsky reagent.

 

OL paper

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

Alkyne hydrothiolation with Wilkinson’s catalyst

Posted by naturalproductman on January 27, 2016

Jennifer Love and co-workers from the University of British Columbia reported in Organic Letters on the use of Wilkinson’s catalyst to perform a hydrothiolation reaction across an alkyne to synthesize K777, a cysteine protease inhibitor.

 

OL paper

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

Fusarisetin A synthesis

Posted by naturalproductman on January 27, 2016

Yandong Zhang and co-workers at Xiamen University have reported in Organic Letters on a synthesis of fusarisetin A using a one pot intramolecular Diels-Alder/Mukaiyama aldol reaction cascade sequence.

OL paper

Posted in Cascade Reactions, Diels-Alder, Named Reactions, One pot, Total Synthesis | Leave a Comment »

Vesparioside B synthesis

Posted by naturalproductman on January 26, 2016

Jin-Song Yang and co-workers from Sichuan University have reported in JACS on the synthesis of vesparioside B.

 

JACS paper

Posted in Glycosides, Total Synthesis | Leave a Comment »

Ileabethoxazole, Pseudopteroxazole, and seco-Pseudopteroxazole syntheses

Posted by naturalproductman on January 26, 2016

Ang Li and co-workers from SIOC have reported in ACIE on the syntheses of three diterpenoids.

 

ACIE paper

Posted in Diterpenoids, Total Synthesis | Leave a Comment »

From carboxylic acid to ketone

Posted by naturalproductman on January 26, 2016

Peter Schreiner and co-workers from Justus-Liebig University have reported in ACIE on an asymmetric Dakin-West reaction. I am reminded of a similar transformation from carboxylic acid chlorides to trifluoroketones reported by Samir Zard’s group. From my own experience, the Zard reaction also works with just a carboxylic acid as the starting material (except, as pointed out – is not an asymmetric reaction).

 

ACIE paper

Posted in Asymmetric, Cascade Reactions, Dakin-West, Methodology, Named Reactions | 2 Comments »