6333-10-4Relevant academic research and scientific papers
Access to Enantiopure Triarylmethanes and 1,1-Diarylalkanes by NHC-Catalyzed Acylative Desymmetrization
Lu, Shenci,Song, Xiaoxiao,Poh, Si Bei,Yang, Hui,Wong, Ming Wah,Zhao, Yu
supporting information, p. 2275 - 2281 (2017/02/23)
We present herein an unprecedented, efficient and enantioselective synthesis of triarylmethanes and 1,1-diarylalkanes through N-heterocyclic carbene-catalyzed acylative desymmetrization of bisphenols. This method utilizes readily available substrates, reagents and a simple procedure to deliver the valuable products in excellent enantiopurity. DFT calculations reveal that the selectivity is governed by the C?C bond cleavage step of the tetrahedral intermediate leading to the ester product. A transition state model featuring a combination of intramolecular hydrogen bond and steric effect is developed to explain the enantioselectivity.
Phosphotriester oligonucleotides, amidites and method of preparation
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, (2008/06/13)
Oligonucleotides having bioreversible phosphate blocking groups can be used as pro drugs for the oligonucleotides. The bio-reversible blocking groups can be removed by intercellular enzymes, particularly carboxyesterases, to provide the unprotected oligonucleotide. The oligonucleotides can be prepared via post synthesis alkylation reactions or utilizing amidite type chemistry wherein the bioreversible phosphorus protecting group is formed as an integral part of the amidite reagent.
