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In this work, we thoroughly analyze the structural behavior of 3-pyrroline (unsaturated analogue of pyrrolidine) in the context of generating possible clathrate hydrates. The crystals of neat amine and its two hydrates tri- and hexahydrate have been obtained with the in situ crystallization technique assisted by IR laser focused radiation. The neat amine crystallizes in the P21 /c space group with three ordered nonequivalent amine molecules in the unit cell. The structure of 3-pyrroline trihydrate is characterized by layers formed by amine and water molecules (P21 /c), whereas 3-pyrroline hexahydrate contains amine moieties incorporated in a three-dimensional water network, thus resembling hydrates characteristic for kosmotropes. The latter system is isostructural with pyrrolidine hexahydrate and undergoes a phase transition (P21 /m ↔ Cmcm). The analyses were completed by PXRD experiments performed for mixtures with different ratios of amine to water, Raman spectroscopy, differential scanning calorimetry studies, and ab initio calculations. A relatively small change in the ring of 3-pyrroline in comparison to fully saturated pyrrolidine seems to not affect the kosmotropic behavior of the molecule described here. This is not the case of a ring size which is the key feature defining the kosmo- or chaotropic character of the compounds. Indeed, the six-membered piperidine tends to form hydrates characteristic for chaotropes.

Complexes containing aminophenolate ligands are considered as very efficient initiators of ring‐opening polymerization (ROP). Our systematic studies of the reactions of two selected aminophenols, 2‐[(p‐tolylamino)methyl]‐4‐(2,4,4‐trimethylpentan‐2‐yl)phenol (L'H2) and 2‐cyclohexylaminomethyl‐4‐methylphenol (L″H2), with alkyl compounds of aluminium, gallium and zinc resulted in the formation of a variety of products depending on the type of metallic centre and alkyl groups bonded to metal atoms. New trinuclear aluminium complexes (Me5Al3(L′)2 (1) and Me5Al3(L″)2 (2)), monomeric aluminium (tBu2Al(L'H) (3) and tBu2Al(L″H) (5)) and gallium (tBu2Ga(L'H) (4) and tBu2Ga(L″H) (6)) compounds, and dinuclear gallium (Et2Ga(L″H)·Et3Ga (7)) and zinc (tBuZn(L″H)]2 (8)) complexes were isolated and characterized. The molecular and crystal structures of 7 and 8 were determined on the basis of an X‐ray diffraction study. Polymerization tests showed that only three complexes (6–8) had activity in the ROP of ε‐caprolactone, whereas 1–5 were inactive in ROP.

Reactions of organomagnesium halides with group 13 metal halides lead to the formation of R3M type compounds (R = alkyl, aryl; M = Al, Ga, In) and are considered as the simplest methods of R3M compound syntheses. These seemingly simple reactions reveal a much more complex chemistry involving mixed magnesium‐group 13 metal compounds. To elucidate the reaction course of reactions of organomagnesium halides with group 13 metal halides, we have studied reactions of R3M with organomagnesium halides. The interaction of Et3M with R1MgX led to the formation of following products being mixtures of crystalline ionic complexes with the general composition of [Et4‐nR1nM]−[XMg (thf)5]+·(thf): [Et2.2Al(CH=CH2)1.8]−[BrMg (thf)5]+·(thf) (1), [Et3Ga(CH=CH2)]−[BrMg (thf)5]+·(thf) (2), [Et4Al]−[BrMg (thf)5]+·(thf) (3), [Et4Ga]−[BrMg (thf)5]+·(thf) (4), [Et2.9Al(C6H5)1.1]−[BrMg (thf)5]+·(thf) (5), [Et2.9Ga(C6H5)1.1]−[BrMg (thf)5]+·(thf) (6), [Et3.4GaMe0.6]−[IMg (thf)5]+·(thf) (7) and [Et4In]−[BrMg (thf)5]+·(thf) (8). A comparison of the production course of group 13 metal trialkyls R3M with a thermal decomposition of 1–8 products showed that reactions of MX3 with RMgX (X = Br, I; R = alkyl, aryl) yield initially intermediate ionic compounds, which must then be thermally decomposed to obtain pure R3M compounds. If group 13 metal bromides and iodides, and alkyl (aryl)magnesium bromides and iodides in thf are used, only intermediate products with the [R4M]−[XMg (thf)5]+·(thf) structure are formed.

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