D-Camphorsulfonic acid

DL-2-Thio-1 -phenyl-imidazolidine 1,2-Dibromoethane d-10-Camphorsulfonic acid... 

For MCD measurements, the instrument is calibrated using the natural CD of D-10-camphorsulfonic acid as a standard. The magnetic field is determined with freshly prepared hexacyanoferrate ion, Ae422//7 = 3.0 (cm M T)"1, where IT = 10000 G. When the direction of the magnetic field is parallel to the Poynting vector,... 

Figure B3.5.7 CD spectrum of D-(+)-10-camphorsulfonic acid (CSA) in water. The vertical bars represent variations of 1.5% and 5%. The broken line represents the extrapolation of a gaussian band. Commercial CSA was twice recrystallized. (From Chen and Yang, 1977.)...

D-10-camphorsulfonic acid is added to a benzene solution of the pyrrolidine enamine of a-phenylpropionaldehyde. Then water is... 

Similar asymmetric induction is observed on halolactonization of 7,8-unsaturated thioamides. These substrates, unlike the amides, undergo highly selective protiothiolac-tonization with d-( + )-10-camphorsulfonic acid. 

A new method for the resolution of ketones depends upon the formation of an iminium salt containing an optically active anion.2 A ketone of one type, exemplified by (1), is converted into the pyrrolidine enamine (2), which is then treated with d-10-camphorsulfonic acid (3) to give the salt (4), which was resolved by systematic crystallization. Each enantiomeric salt was then crystallized and hydrolyzed to a pure enantiomeric ketone (1). 

Resolution p-Boronobenzoic acid. d-10-Camphorsulfonic acid. Di-p-toluoyl-L-tartrate, see Hydrazoic acid. Iodobenzenedichloride. d- and /-a-Methylbenzylamine. 1-Phenylethane-sulfonic acid, see l,3-Dibenzyl-2-methyl-l, 3,2-diazaphospholidine. (+) and (-)-a-)2,4,5,7-Tetranitro-9-fluorenylideneaminooxy)-propionic acid. 

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