Probing electronic effects in the asymmetric Heck reaction with the BIPI ligands.

Org Lett

Department of Chemical Development, Boehringer-Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Rd., Ridgefield, Connecticut 06877, USA.

Published: February 2003

[structure: see text] The new BIPI ligands are phosphinoimidazolines that can be electronically tuned in three different ligand regions to explore electronic effects in asymmetric catalysis. Their application to the asymmetric Heck reaction (AHR) in the creation of a chiral quaternary center is described. Enantioselectivity is shown for the first time to depend linearly on phosphine electron density. Changing the ligand basicity by variation of the R(2) or R(3) substituents reverses facial selectivity.

Download full-text PDF

Source
http://dx.doi.org/10.1021/ol0340179DOI Listing

Publication Analysis

Top Keywords

electronic effects
8
effects asymmetric
8
asymmetric heck
8
heck reaction
8
bipi ligands
8
probing electronic
4
reaction bipi
4
ligands [structure
4
[structure text]
4
text] bipi
4

Similar Publications

The emerging field of quantum life science combines principles from quantum physics and biology to study fundamental life processes at the molecular level. Quantum mechanics, which describes the properties of small particles, can help explain how quantum phenomena such as tunnelling, superposition, and entanglement may play a role in biological systems. However, capturing these effects in living systems is a formidable challenge, as it involves dealing with dissipation and decoherence caused by the surrounding environment.

View Article and Find Full Text PDF

Objective: This systematic review was conducted to examine the impact of education on nutritional knowledge for cancer prevention using the Health Belief Model.

Methods: Comprehensive searches were performed in international electronic databases, including Scopus, PubMed, and Web of Science, from their inception until June 16, 2024. Keywords derived from Medical Subject Headings such as "Nutrition Knowledge," "Education," "Health Belief Model," and "Cancer" were utilized.

View Article and Find Full Text PDF

Impact of comorbidity on survival in cancer patients receiving immune checkpoint inhibitors.

Clin Transl Oncol

January 2025

Medical Oncology Department, Faculty of Medicine, School of Medicine, Cebeci Hospital, Ankara University, Dikimevi, 06590, Ankara, Turkey.

Purpose: Immunotherapy efficacy in elderly patients with comorbidities and poor performance status is not well understood. More knowledge on this topic is needed to identify subgroups that will benefit from immunotherapy. We aimed to evaluate the effect of comorbidity burden in patients receiving immunotherapy.

View Article and Find Full Text PDF

In recent years, carbon dots (CDs) with fluorescence imaging function have been widely used in biomedicine, electronic manufacturing and environmental monitoring. However, monochromatic fluorescence is often limited by the application environment and loses its effectiveness. Here, we carefully designed white fluorescent CDs (WF-CDs) by solvothermal method, which is used for fluorescence imaging applications under different environmental conditions.

View Article and Find Full Text PDF

People who spend time at the beach at increased risk for ultraviolet light (UV) exposure. This review assessed skin cancer-related knowledge, attitudes, beliefs, and prevention practices among beachgoers and sunbathers at the beach. Relevant articles were search in the following electronic databases: PubMed (Medline), Cumulative Index to Nursing and Allied Health (CINAHL), ERIC, and PsycINFO.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!