Catalytic 1,3-Diene Synthesis via C(alkenyl)–H Activation

In an Article appearing online today in J. Am. Chem. Soc., the Engle lab and Liu lab (U Pittsburgh) report a detailed study of palladium(II)-catalyzed C(alkenyl)–H activation, including optimization of a method to prepare structurally diverse 1,3-dienes, organometallic synthesis of key intermediates relevant to catalysis, and experimental/computational studies to interrogate the reaction mechanism. Congrats to the whole team: Mingyu, Pusu, and Malkanthi from Scripps; and Yanyan from Pitt. Special shout out to undergraduate co-author Pusu, who was a visiting student from Nankai university for six months. Thanks to the Liu lab for another fruitful collaboration! Way to go, everyone! Click here for a link to the paper.

diene

Keary Receives 2018 Bayer Early Excellence in Science Award

Congratulations to Keary, who was selected as a recipient of the prestigious 2018 Bayer Early Excellence in Science Award. The prize is awarded by an independent scientific committee of Bayer Science & Education Foundation and will be presented on June, 25 at the Bayer Foundation Day in Berlin. Congratulations to Keary and the entire Engle lab!

For a link to the Bayer press release, click here.
For a link to the TSRI News & Views highlight, click here.

Catalytic, enantioselective method for allenyl boronate synthesis accepted for publication

Our manuscript describing a method to achieve catalytic, enantioselective 1,4-hydroboration of 1,3-enynes was accepted for publication in ACS Catal. Congratulations to the authors, De-Wei, Yiyang (Elaine), Mingyu, Zhen, Malkanthi, Jason, and Keary. We would also like to acknowledge our collaborators at Boehringer-Ingelheim, Dan Fandrick, Jeff Song, and Chris Senanayake, for valuable discussion and guidance. BI has a longstanding interest in allenyl boronates and related organoboron nucleophiles. (For representative papers, see: J. Am. Chem. Soc. 20101327600Org. Lett.20101288Org. Lett. 201113, 5616). Their interest in and experience with this family of compounds played an important role in the genesis of this project, and the Engle lab is looking forward to many stimulating interactions with the BI team moving forward. Click here for a link to the paper. A pre-print of this work was previously published on ChemRxiv (click here).

allenyl

IMG_0195(not pictured: Yiyang (Elaine) and Mingyu)

judging at the orange county science fair

Andrew, Tanner and David headed up to OC for the day to help judge the high school and junior high county science fair. We awarded the “Engle Lab Prize” to an individual who did not get the result they wanted but showed persistence and dedication to their research. In the senior division we awarded the prize for the work done on monitoring sugar conversion in bananas by varying ethylene levels, and in the Junior division for the poster on measuring “sugar” concentration of different types of sugar by quantifying the amount of CO2 produced during fermentation. Congratulations to the winners of the Engle Lab Prize and all the other participants for their great work!

 

Chan–Lam N- and O-cyclopropylation (Pfizer collaboration)

Together with a team from Pfizer Medicinal Chemistry Oncology, we report a new method to append cyclopropyl groups to phenols and aza-heterocycles via Chan–Lam coupling in a manuscript appearing today in J. Org. Chem. The transformation exhibits good functional group tolerance with compatibility with functional groups and heterocycles that are commonly encountered in drug discovery. Using computational ADME tools, we also dug into Pfizer’s data to explore the effect of various cyclopropyl-to-alkyl transforms on clearance rates, illustrating the unique properties of the cyclopropyl group in drug discovery. Congrats to the entire team, Joe, Miriam, Matt, Mark, Ryan, Fen, Michelle, Indra, and special thanks to all the folks from Pfizer for a great collaboration! Click here for a link to the paper.

chan-lam.png

(not pictured: Mark)

Sri Departs for BBRC

The Engle lab bids farewell to a tremendously talented postdoc, Sri, who will be starting the next chapter of his professional life at the Biocon Bristol-Myers Squibb Research Center in Bangalore, India. After a proper send-off at Brewski’s Bar and Arcade, Sri wrapped up his project, got his final fill of Mexican food, and set off for a two-day journey to India. Congratulations on your new position, and thanks for teaching us all about asymmetric catalysis, Sri!

 

Axial chirality made easy

The Engle lab reports its first foray into the world of CuH catalysis, with De-Wei, Yiyang (Elaine), Mingyu, Zhen, and Malkanthi describing a new method to prepare enantioenriched allenyl boronates from terminal enynes. A pre-print of this work appears online today at ChemRxiv (click here). Congratulations to all of the authors, especially undergraduate co-author Elaine. Special thanks to Jason Chen, Director of the TSRI Automated Synthesis Facility,  for super-helpful guidance regarding difficult separations and a great collaboration.

allenyl BPin

Rohan completes his internship

Rohan caps off a great month in the Engle lab with a wrap-up presentation to a group of underclassman and a teacher from High Tech High International. Rohan will return to coursework Monday equipped with valuable hands-on learning experience as he plans further education in chemistry. Props to Rei for awesome mentorship! Thanks for a great four weeks, Rohan — you will be missed!

 

Borylative Alkene 1,2-Difunctionalization Methodology Now Online

In a paper appearing today in the Just Accepted section of J. Am. Chem. Soc., we describe new methodology to carry out directed, borylative 1,2-difunctionalization of alkenes with various carbon/nitrogen nucleophiles and B2pin2 as the reaction partners. Notably, the reaction works with substrates containing an alkene that is distal from the directing group via a 6-membered palladacycle intermediate. Congrats to the authors, Zhen, Hui-Qi, and May! And special props to undergrad co-authors Hui-Qui and May! Click here for a link to the paper.

borylation

20180207_195852(not pictured: Hui-Qi)