All asymmetric objects are dissymmetric, and an object with no improper rotation axis must also be dissymmetric.
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The synthesis of dissymmetric, bidentate ligand precursors was attempted in a sequential derivatization of the diamine.
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Described here are systems in which symmetrical molecules assemble through hydrogen bonding to produce capsules with dissymmetric cavities.
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The chiral efficiency of BINAP is a result of dissymmetric templates created by a transition metal atom and the C2 chiral diphosphine.
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The park has a tropical dissymmetric climate. The mean annual temperatures are 32.9 °C (maximum) and 24.3 °C (minimum). Rainfall ranges from 522 to 2,135 mm, with an average annual rainfall of 1,215 mm. The summer season in April and May determines the peculiar vegetation of the Coromandel-Circar coast.
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Some inherently chiral molecules contain chirality planes, or planes within a given molecules across which the molecule is dissymmetric. Paracyclophanes often contain chiral planes if the bridge across the phenylene unit is short enough, or if the phenylene contains another substituent, not in the bridge, that hinders rotation of the phenylene unit.
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Lupinine is naturally biosynthesized from l-lysine in the Lupinus genes of plants along with various other quinolizidine alkaloids. In the biosynthetic process, lysine is first decarboxylated into cadaverine, which is then oxidatively deaminated to the corresponding aldehyde. The aldehyde is then spontaneously cyclized into two tautmers which couple through an aldol type mechanism in which the allylic amine attacks the iminium, forming a dissymmetric dimeric intermediate which is then hydrated. The primary amine is then oxidized and an intramolecular condensation occurs, giving the quinolizidinealdehyde.
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An planar chiral derivative of ferrocene, used for kinetic resolution of some racemic secondary alcohols This term is used in chemistry contexts, e.g., for a chiral molecule lacking an asymmetric carbon atom, but possessing two non-coplanar rings that are each dissymmetric and which cannot easily rotate about the chemical bond connecting them: 2,2'-dimethylbiphenyl is perhaps the simplest example of this case. Planar chirality is also exhibited by molecules like (E)-cyclooctene, some di- or poly-substituted metallocenes, and certain monosubstituted paracyclophanes. Nature rarely provides planar chiral molecules, cavicularin being an exception.
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N-tosylated derivative, TsDPEN, is a ligand precursor for catalysts for asymmetric transfer hydrogenation. For example, (cymene)Ru(S,S-TsDPEN) catalyzes the hydrogenation of benzil into (R,R)-hydrobenzoin. In this reaction, formate serves as the source of H2: :PhC(O)C(O)Ph + 2 H2 → PhCH(OH)CH(OH)Ph (R,R isomer) This transformation is an example of desymmetrization, the symmetric molecule benzil is converted to the dissymmetric product. DPEN is a key ingredients of Ryōji Noyori's 2nd generation ruthenium-based chiral hydration catalyst, for which he earned the Nobel Prize in Chemistry in 2001.
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