161344-72-5Relevant academic research and scientific papers
Sigmatropic -Wittig Rearrangement of α-Allylic-Heterosubstituted Methylphosphonates. Part 3: High Diastereoselectivity in the Rearrangement of Anion of Dimethyl Allyloxymethylphosphonate
Gulea-Purcarescu, Mihaela,About-Jaudet, Elie,Collignon, Noel
, p. 6635 - 6638 (1995)
A diastereoselectivity up to 90percent was achieved in the title rearrangement of lithiated allyloxymethylphosphonates, by using the cheaply available chiral dimenthylphosphonyl ester group as stereodirecting auxiliary.The absolute configuration of the newly formed chiral center was assigned by usual chemical conversions.
Solvent-assisted monomeric molecular structure of the phosphate diester and the synthesis of menthol-based phosphate diesters
Mandal, Debdeep,Gupta, Vivek,Santra, Biswajit,Chrysochos, Nicolas,Bhoyare, Vivek W,Maiti, Avijit,Kar, Abhisek,Suman,Guha, Anku,Thakur, Pallavi,Narayanan, Ramakirushnan Suriya,Patil, Nitin T,Schulzke, Carola,Chandrasekhar, Vadapalli,Jana, Anukul
, (2019/12/14)
Abstract: Phosphate diesters are well known to form intermolecular H-bonded dimeric structures in their solid-state. Recently, we reported 2,6-(CHPh)2-4-iPr-phenyl substituted phosphate diester exists as H-bonded monomeric molecular structure a
Planar chirality from the chiral pool: Diastereoselective anionic phospho-fries rearrangements at ferrocene
Korb, Marcus,Lang, Heinrich
, p. 6643 - 6659 (2015/02/19)
Exclusively, the anionic phospho-Fries rearrangement has successfully been adopted on chiral ferrocenyl phosphates, resulting in diastereomeric enriched 1,2-P,O-phosphonates (up to 95% de), which can further be converted to an enantiomerically pure phosphane. A simple synthetic protocol for the preparation of all starting materials based on several chiral-pool alcohols, chiral (di)chlorophosphates, and the respective ferrocenyl phosphates is reported. Optimized reaction conditions for the anionic phospho-Fries rearrangement allow conversions at ambient temperature and the use of variable lithium amid bases and diamines in hexane, ensure virtually quantitative yields, and avoid side reactions. The (bi)cyclic alkyl substituents result in air- and moisture-stable compounds and furthermore allow the conversion of 1,1′-substituted derivatives to 1,1′,2,2′-functionalized ferrocenes, which is reported for the first time. Simultaneous rearrangements at diferrocenyl phosphates to phosphinates and even 2-hydroxy-1,3-bis(phosphonato) ferrocenes and their workup under ambient conditions can be performed. Single-crystal diffraction analysis allowed the determination of the absolute configuration of the planar chirality of two diastereomerically pure ferrocenes being the Rp isomers. Furthermore, strong T-shaped π-π interaction patterns between aromatic C5H3 and C5H4 cycles for three compounds are observed.
Rearrangements of Nonracemic Vinyl Phosphates to β-Keto Phosphonates
An, Yi-Zhong,An, Jian Guo,Wiemer, David F.
, p. 8197 - 8202 (2007/10/02)
A series of chiral auxiliaries has been tested for viability in the vinyl phosphate/β-keto phosphonate rearrangement.While dienyl phosphates derived from ephedrine, pseudoephedrine, and isopinocampheol succumbed to competing elimination reactions, ones derived from menthol and (S)-2-methylbutanol were found to undergo rearrangement to the desired β-keto phosphonates.The bis((S)-2-methylbutyl) phosphorochloridate then was used to prepare the vinyl phosphates of the prochiral ketone 4-methylcyclohexanone, and modest diastereoselectivity was observed upon rearrangement of these phosphates to the corresponding β-keto phosphonates.The de of this rearrangement was established by degradation of the β-keto phosphonate to 3-methyladipic acid and determination of the optical rotation.This sequence allowed identification of the major rearrangement product as the 4R-diastereomer of β-keto phosphonate 13.Finally, two other prochiral cyclohexanones were found to be suitable substrates for the vinyl phosphate/β-keto phosphonate rearrangement.
