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1-Phenylpiperazine (1-PP or PP) is a simple chemical compound and drug featuring a phenyl group bound to a piperazine ring. [1] The suffix ‘-piprazole’ is sometimes used in the names of drugs to indicate they belong to this class. [2] It is a rigid analogue of amphetamine.
Other NMR-active nuclei can also cause these satellites, but carbon is most common culprit in the proton NMR spectra of organic compounds. Sometimes other peaks can be seen around 1 H peaks, known as spinning sidebands and are related to the rate of spin of an NMR tube. These are experimental artifacts from the spectroscopic analysis itself ...
The spin interaction that is usually employed for structural analyses via solid state NMR spectroscopy is the magnetic dipolar interaction. [8] Additional knowledge about other interactions within the studied system like the chemical shift or the electric quadrupole interaction can be helpful as well, and in some cases solely the chemical shift has been employed as e.g. for zeolites. [9]
All stereoisomers of a certain class of compounds are synthesized, and their proton NMR and carbon-13 NMR chemical shifts and coupling constants are compared. Yoshito Kishi's group at Harvard University has reported NMR databases for 1,3,5-triols [1] 1,2,3-triols, 1,2,3,4-tetraols, and 1,2,3,4,5-pentaols. [2]
Aromatic ring currents are relevant to NMR spectroscopy, as they dramatically influence the chemical shifts of 1 H nuclei ("protons") in aromatic molecules. [2] The effect helps distinguish these nuclear environments and is therefore of great use in molecular structure determination.
The types of NMR usually done with nucleic acids are 1 H or proton NMR, 13 C NMR, 15 N NMR, and 31 P NMR. Two-dimensional NMR methods are almost always used, such as correlation spectroscopy (COSY) and total coherence transfer spectroscopy (TOCSY) to detect through-bond nuclear couplings, and nuclear Overhauser effect spectroscopy (NOESY) to ...
Two common salts in the form of which piperazine is usually prepared for pharmaceutical or veterinary purposes are the citrate, 3C 4 H 10 N 2 ·2C 6 H 8 O 7 (i.e. containing 3 molecules of piperazine to 2 molecules of citric acid), and the adipate, C 4 H 10 N 2 ·C 6 H 10 O 4 (containing 1 molecule each of piperazine and adipic acid). [6]
The structures of common lithium amides, such as lithium diisopropylamide (LDA) and lithium hexamethyldisilazide (LiHMDS) have been extensively studied by Collum and coworkers using NMR spectroscopy. [17] Another important class of reagents is silyllithiums, extensively used in the synthesis of organometallic complexes and polysilane dendrimers.