作者:Ali A. Kandil、Terence M. Porter、Keith N. Slessor
DOI:10.1055/s-1987-27968
日期:——
Phosphonates possessing α-electron withdrawing functionalities can be readily prepared by treatment of nitriles, nitroalkanes, and esters with 2 molar equivalents of base followed by phosphonylation with diethyl chlorophosphate.
Synthesis of the cis diastereoisomer of 5-diethoxyphosphoryl-5-methyl-3-phenyl-1-pyrroline N-oxide (DEPMPPOc) and ESR study of its superoxide spin adduct
prepared in three steps from phenylacetaldehyde and used in ESR-spin trapping of various carbon-, oxygen- and sulfur-centred radicals. In the case of the cis-isomer, the presence of the phenyl group cancels the alternating line width phenomenon observed for the DEPMPO–OOR (R = H, But) spin adducts. The ESR spectra of the DEPMPPOc–OOR spin adducts exhibit more straightforward patterns and are more easily
由苯乙醛分三步制备5-二乙氧基磷酰基-5-甲基-3-苯基-1-吡咯啉N-氧化物(DEPMPPO)的顺式和反式非对映异构体,并将其用于ESR -自旋捕获各种以碳,氧和硫为中心的自由基。在顺式异构体的情况下,苯基的存在消除了DEPMPO-OOR(R = H,Bu t)自旋加合物的交替线宽现象。DEPMPPO c -OOR自旋加合物的ESR谱图显示出更简单的图案,并且更易于分配。
A diastereo- and enantioselective synthesis of α-substituted anti-α,β-diaminophosphonic acid derivatives
作者:Jeremy C. Wilt、Maren Pink、Jeffrey N. Johnston
DOI:10.1039/b808393b
日期:——
Highly diastereo- and enantioselective additions of alpha-nitrophosphonates to imines catalyzed by a chiral Bronsted acid are described.
Enantioselective Synthesis of α-Amino-γ-sulfonyl Phosphonates with a Tetrasubstituted Chiral α-Carbon<i>via</i>Quinine-Squaramide-Catalyzed Michael Addition of Nitrophosphonates to Vinyl Sulfones
作者:Kalisankar Bera、Irishi N. N. Namboothiri
DOI:10.1002/adsc.201300224
日期:2013.5.3
α‐Nitro‐γ‐sulfonylphosphonates with a key tetrasubstituted chiral α‐carbon center have been synthesized for the first time in high yield and enantioselectivity through a quinine‐squaramide‐catalyzed conjugate addition of α‐nitro phosphonates to aryl vinyl sulfones. Representative examples presented here for the transformation of nitrosulfonyl phosphonates to aminosulfonyl phosphonates, alkylation