Dimethylmalonyltrialkylphosphoranes: New General Reagents for Esterification Reactions Allowing Controlled Inversion or Retention of Configuration on Chiral Alcohols
作者:James McNulty、Alfredo Capretta、Vladimir Laritchev、Jeff Dyck、Al J. Robertson
DOI:10.1021/jo026639y
日期:2003.2.1
through reaction of a trialkylphosphine with 2-chlorodimethylmalonate in the presence of triethylamine. These new reagents promote the condensation reaction of carboxylic acids with alcohols to provide esters along with trialkylphosphine oxide and dimethylmalonate. The condensation reaction of chiral secondary alcohols can be controlled to give either high levels of inversion or retention through a
Efficient Method for the Preparation of Carboxylic Acid Alkyl Esters or Alkyl Phenyl Ethers by a New-Type of Oxidation–Reduction Condensation Using 2,6-Dimethyl-1,4-benzoquinone and Alkoxydiphenylphosphines
A new-type of oxidation–reduction condensation proceeded smoothly to afford carboxylic acid alkyl esters or alkyl phenyl ethers in good to high yields by combined use of alkoxydiphenylphosphines (1...
synthesized and evaluated for their antibacterial activity against Gram-positive Staphylococcus aureus and Bacillus subtilis and Gram-negative Escherichia coli and in vitro antifungal activity against Candida albicans and Aspergillus niger. The results of antimicrobial activity demonstrated that the compounds 10, 20, and 21 were the most active ones among the synthesized compounds. The QSAR studies revealed
Cohen; Dudley, Journal of the Chemical Society, 1910, vol. 97, p. 1747
作者:Cohen、Dudley
DOI:——
日期:——
The presence of an event in the narrated situation affects its availability to the comprehender
作者:Rolf A. Zwaan、Carol J. Madden、Shannon N. Whitten
DOI:10.3758/bf03209350
日期:2000.11
Narrative descriptions of events often depart from how these events would have occurred in "real time." For example, narratives often contain time shifts in which events that are irrelevant to the plot are omitted. Zwaan (1996) has shown that these time shifts may affect on-line comprehension. Specifically, they are associated with increases in processing load and a deactivation of previous information. The experiments in the present article show that the situation is more complex. Specifically there is only a deactivation of previous events if they are not assumed to be ongoing after a time shift. Furthermore, explicit discontinuations of events, as in he stopped walking also lead to deactivations when compared with explicit continuations and resumptions.