Mathematic rule and the experiments of chiral enhancement/amplification for enantiomers before origin of life

Abstract

The non-racemic enantiomers may exist with very small %ee values, which formed by some asymmetric factors (such as symmetry breaking) during their synthesis in the prebiotic pool in the absence of other chiral sources. We now conclude a mathematic formula by concerning the organic reaction principles. We found that the tiny %ee (%ee1) values of non-racemic enantiomers can be enhanced to a reasonable large %ee values (%ee2) after the non-racemic enantiomers react with bis-functional group reagents (such as oxalaldehyde). Theoretically, if the %ee1 is extremely small, the enhancement/amplification multiples (%ee2/%ee1) should increase greatly. The is necessary to enrich the %ee values in prebiotic pool for the chiral compounds (such as L-amino acids) with very small %ee values. Finally, about 1% of L-tryptophan methyl ester （L-TME） was used to react with CHOCHO, and the %ee2 of the L-TME remained in solution increased to 3.4%. The largest amplification multiple is 1.9 (from 6.1% of %ee1 to enrich to 11.7% (%ee2)); The largest increasement of the %ee (Δ%ee=%ee2-%ee1) is 12.3% (from 44.2% to 56.5%).

Keywords

• computational chemistry; chiral enrichment/amplification; enantiomers; prebiotic era; l-amino acids