The use of (4r,5r)-dicarboalkoxy 2-chloro 1,3,2-dioxaphospholanes as new chiral derivatizing agents for the determination of enantiomeric purity of alcohols by 31P NMR.

An efficient chiral phosphorus derivatizing agent for the determination of the enantiomeric excess of chiral alcohols and amines by 31P NMR spectroscopy

“…Moreover, we also compared the outcomes obtained by the use of CDA 1 with the results determined by polarimetry (entries [12][13][14]. We found that they agreed well with each other.…”

Activation of molecular oxygen and its use in stereoselective tetrahydrofuran-syntheses from δ,ε-unsaturated alcohols

“…Diastereoselectivity of the latter corresponded to values determined for hydroxylsubstituted derivatives 10b-d. Enantiomeric purities of alcohols 10b-d were checked via 31 P-NMR, after derivatization with a chiral dioxaphospholane. 31 Products 10b-d were consistently formed as racemates. This result was independent from whether samples from an early phase of the reaction or after complete consumption of substrates 9b-d were collected for derivatization.…”

“…The product was obtained as a racemate, regardless whether the material was isolated at conversions below or above 50%. Its enantiomeric purity was determined by 31 P NMR with the aid of a chiral phosphorous-based derivatization reagent. 31 No conversion of 9a took place, upon substituting Co(OAc) 2 •4H 2 O for, e.g., complex 6 (GC).…”

“…Its enantiomeric purity was determined by 31 P NMR with the aid of a chiral phosphorous-based derivatization reagent. 31 No conversion of 9a took place, upon substituting Co(OAc) 2 •4H 2 O for, e.g., complex 6 (GC). Purging of O 2 through solutions of 6 and alkenol 9a in 2-propanol at 60 • C furnished complete turnover of the substrate, however, without providing a satisfactory mass balance (not shown).…”

(4R,5R)-Bis(N,N-dimethylaminocarbonyl)-2-chloro-1,3,2-dioxaphospholane: A convenient reagent for control of enantiomeric composition of chiral alcohols by31P NMR spectroscopy

“…4 The use of (4R,5R)-diethoxycarbonyl-2-chloro-1,3,2-dioxaphospholane (1) for control of the enantio- Reactions with these bonds result in the formation of the R*O--P bonds.…”