Chirality arising from isotope substitution, especially with atoms heavier than the hydrogen isotopes, is usually not considered a source of chirality in a chemical reaction. An N 2 ,N 2 ,N 3 ,N 3‐tetramethyl‐2,3‐butanediamine containing nitrogen (14N/15N) isotope chirality was synthesized and it was revealed that this isotopically chiral diamine compound acts as a chiral initiator for asymmetric autocatalysis.

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Chirality arising from isotope substitution, especially with atoms heavier than the hydrogen isotopes,i su sually not considered as ource of chirality in ac hemical reaction. An N 2 ,N 2 ,N 3 ,N 3 -tetramethyl-2,3-butanediamine containing nitrogen ( 14 N/ 15 N) isotope chirality was synthesized and it was revealed that this isotopically chiral diamine compound acts as ac hiral initiator for asymmetric autocatalysis. Most of the chemical elements have stable isotopes.Isotope-substituted compounds (isotopomers) have almost the same chemical reactivity,isotope substitution and isotope effect, therefore they are widely used for studies of reaction mechanisms and tracing compounds.[1] However,i sotope substitution sometimes breaks the molecular symmetry and produces hidden chirality in usually achiral molecules. Usually,this hidden chirality does not receive much attention because the difference between these isotopically chiral compounds is very small and negligible in asymmetric induction. Although the chirality arising from isotope substitution was discussed after the finding of stable isotopomers, [2][3][4] the isotope effect in chirality has mainly been studied on hydrogen isotopes because the almost double relative mass ratio of Ha nd Dp roduces relatively large isotope effects compared with other element isotopomers.[5] Thus,c hirality induction in areaction arising from heavier atoms [6] is ahighly challenging and interesting topic, especially in the study of the origin of homochirality. [7] We have been studying asymmetric autocatalysis of pyrimidyl alkanol, [8] which causes significant amplification of enantiomeric excess (ee)during the progress of areaction. This reaction can recognize the various chiral environments [9] and attracts wide attention from the viewpoint of symmetry breaking [10] and its unique reaction mechanism.[11] Recently, we demonstrated that asubtle difference of isotopic chirality can induce asymmetric induction in an asymmetric autocatalysis reaction.[12] Chiral compounds (as the result of hydrogen (H/D), [13] carbon ( 12 C/ 13 C), [14] and oxygen ( 16 O/ 18 O) [15] isotopes) act as chiral initiators for asymmetric autocatalysis. Herein, we report the first example of asymmetric induction by chiral nitrogen ( 14 N/ 15 N) isotopomers with as maller relative mass difference compared to previously reported isotopomers (Scheme 1).Nitrogen is one of the abundant atoms in the construction of various bioorganic molecules,and the coordinating ability of nitrogen atoms is widely exploited in various ligands. 15 Nis auseful NMR-active isotope and the isotope ratio of 14 N/ 15 N is also used in the study of the origin of meteorites. [16] However,t oo ur knowledge,i sotopically chiral compounds arising from nitrogen isotope ( 14 N/ 15 N) substitution have not been synthesized and studied as achiral initiator.Herein, we demonstrate the synthesis of compounds that are isotopically chiral by nitrogen isotope substitution and their chiral induction of asymmetric autocatalysis (S...

Chiralität durch Isotopensubstitution , namentlich mit schwereren Atomen als Wasserstoffisotopen, wird generell nicht als Chiralitätsquelle für chemische Reaktionen angesehen. In der Zuschrift auf S. 15472 ff. nutzen A. Matsumoto, K. Soai et al. ein 14N/15N‐isotopenchirales Diamin, N2,N2,N3,N3‐Tetramethyl‐2,3‐butandiamin, als Initiator für eine asymmetrische Autokatalyse. Dabei gelingt erstmals eine enantioselektive Chiralitätsinduktion ausschließlich auf Grundlage von Stickstoff(14N/15N)‐Isotopensubstitution.

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