126178-04-9Relevant academic research and scientific papers
Preparation and reactions of 2,2-dimethyl-1,3-dioxan-5-one-SAMP-hydrazone: A versatile chiral dihydroxyacetone equivalent
Enders, Dieter,Voith, Matthias,Ince, Stuart J.
, p. 1775 - 1779 (2007/10/03)
The SAMP-hydrazone of 2,2-dimethyl-1,3-dioxan-5-one represents a valuable chiral dihydroxyacetone equivalent. Asymmetric mono- or α,α′-bisalkylations followed by auxiliary cleavage leads to the corresponding mono- or α,α′-disubstituted, acetonide protected ketodiols in excellent diastereo- and enantiomeric excesses.
Asymmetric synthesis of pseudo C2-symmetric 2-methyl substituted 1,3-diols
Enders,Voith
, p. 29 - 32 (2007/10/03)
The diastereo- and enantioselective synthesis of pseudo C2-symmetric, 2-methyl substituted, acetonide protected (4) and free 1,3-diols 5 employing the SAMP-hydrazone mothodology with virtually complete asymmetric induction (de ≥ 96%, ee ≥ 98-99
Iterative asymmetric synthesis of protected anti-1,3-polyols
Enders, Dieter,Hundertmark, Thomas
, p. 4169 - 4172 (2007/10/03)
A new general method for the iterative asymmetric synthesis of anti-1,3-polyol chains has been developed. The α,α'-bisalkylation of 2,2-dimethyl-1,3-dioxan-5-one SAMP-hydrazone 1 with benzyloxymethylchloride as the second electrophile leads to virtually diastereo- and enantiopure substituted 2,2-dimethyl-1,3-dioxan-5-ones with good overall yields. Their deoxygenation and conversion into primary iodides affords the electrophile for the further alkylation of 1. In this way the configurations of all new stereogenic centres are controlled by a single auxiliary.
Diastereo- and enantioselective synthesis of α,α'-disubstituted, C2-symmetric ketones using the SAMP-/RAMP-hydrazone method
Enders,Gatzweiler,Jegelka
, p. 1137 - 1141 (2007/10/02)
Starting from simple, symmetric ketones such as, 3-pentanone,1,3-diphenyl-2-propanone and 2,2-dimethyl-1,3-dioxan-5-one, α,α'-bisalkylation of the corresponding SAMP-hydrazones (S)-2 and (S)-8 [(S)-1 -(alkylideneamino)-2-(methoxymethyl)pyrrolidines and (S)-1-(2,2-dimethyl-1,3-dioxan-5-ylideneamino)-2-(methoxymethyl)pyrroli dines, respectively], followed by oxidative cleavage with ozone affords chiral, C2-symmetric ketones 5 and (S,S)-11 of high diastereo- and enantiomeric purity (de, ee > 98%).
Enantioselective Alkylation of 2,2-Dimethyl-1,3-dioxan-5-one Using the SAMP-/RAMP-Hydrazone Method
Enders, Dieter,Bockstiegel, Bernhard
, p. 493 - 496 (2007/10/02)
The lithiated SAMP-hydrazone (S)-3 is used as a chiral 1,3-dihydroxyacetone-enolate equivalent C in overall enantioselective α-alkylations leading to 4-alkyl-2,2-dimethyl-1,3-dioxan-5-ones (S)-5a-i in good overall chemical yields and of high enantiomeric purity (ee = 88 - >/= 93percent.
