Stereoselective synthesis of amino acid-derived β-lactams. Experimental evidence for TADDOL as a memory of chirality enhancer was written by Bonache, M. Angeles;Lopez, Pilar;Martin-Martinez, Mercedes;Garcia-Lopez, M. Teresa;Cativiela, Carlos;Gonzalez-Muniz, Rosario. And the article was included in Tetrahedron in 2006.Quality Control of ((4S,5S)-2,2-dimethyl-1,3-dioxolane-4,5-diyl)bis(diphenylmethanol) This article mentions the following:
In model experiments, concerning the modulation of memory of chirality during the intramol. alkylation of N-(4-methoxybenzyl)-N-chloroacetyl-Phe-O-tert-Bu derivative to the corresponding β-lactam I, TADDOL was selected from a panel of different phase-transfer catalysts as the best chiral additive (ee up to 82%). We have demonstrated here that the degree and sign of the cyclization selectivity was virtually independent on TADDOL configuration, providing exptl. proof that in this reaction this additive works as a memory of chirality enhancer and not as a real catalyst. The effect of TADDOL is strongly dependent on the starting amino acid derivative, the increase of selectivity being only observed for those with aromatic side chains. In the experiment, the researchers used many compounds, for example, ((4S,5S)-2,2-dimethyl-1,3-dioxolane-4,5-diyl)bis(diphenylmethanol) (cas: 93379-49-8Quality Control of ((4S,5S)-2,2-dimethyl-1,3-dioxolane-4,5-diyl)bis(diphenylmethanol)).
((4S,5S)-2,2-dimethyl-1,3-dioxolane-4,5-diyl)bis(diphenylmethanol) (cas: 93379-49-8) belongs to dioxole derivatives. Dioxoles, particularly fluorinated dioxoles, are used as co-monomers to make polymers that find use in forming protective coatings for chemical resistance. 1,3-Benzodioxole can be synthesized from catechol with disubstituted halomethanes.Quality Control of ((4S,5S)-2,2-dimethyl-1,3-dioxolane-4,5-diyl)bis(diphenylmethanol)
Referemce:
1,3-Benzodioxole – Wikipedia,
Dioxole | C3H4O2 – PubChem