.2.2ryptand is the

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon- hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. Th ...

with the formula N(CH₂CH₂OCH₂CH₂OCH₂CH₂)₃N. This

bicyclic In chemistry, a bicyclic molecule () is a molecule that features two joined rings. Bicyclic structures occur widely, for example in many biologically important molecules like α-thujene and camphor. A bicyclic compound can be carbocyclic (a ...

molecule is the most studied member of the cryptand family of

chelating agent Chelation is a type of bonding of ions and molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a polydentate (multiple bonded) ligand and a single central metal atom. These ligands are ...

s. It is a white solid. Many analogous compounds are known. Their high affinity for alkali metal cations illustrates the advantages of "preorganization", a concept within the area of

supramolecular chemistry Supramolecular chemistry refers to the branch of chemistry concerning chemical systems composed of a discrete number of molecules. The strength of the forces responsible for spatial organization of the system range from weak intermolecular force ...

. For the design and synthesis of .2.2ryptand, Jean-Marie Lehn shared the

Nobel Prize in Chemistry ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then "M ...

. The compound was originally prepared starting with the diacylation of the diamine-diether: : H₂OCH₂CH₂NH₂sub>2 + H₂OCH₂COClsub>2 → H₂OCH₂CH₂NHC(O)CH₂sub>2 + 2 HCl The resulting macrocyclic diamide is reduced by

lithium aluminium hydride Lithium aluminium hydride, commonly abbreviated to LAH, is an inorganic compound with the chemical formula Li Al H4. It is a white solid, discovered by Finholt, Bond and Schlesinger in 1947. This compound is used as a reducing agent in organic ...

. The resulting macrocyclic diamine tetraether reacts with a second equivalent of H₂OCH₂COClsub>2 to produce the macro''bi''cyclic diamide. This di(tertiary)amide is reduced to the diamine by diborane. .2.2ryptand binds K⁺ as an octadentate N₂O₆ ligand. The resulting cation K( .2.2ryptand)⁺ is lipophilic.

References

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