Quest for lithium amidinates containing adjacent amino donor group at the central carbon atom

New Lanthanide Alkynylamidinates and Diiminophosphinates

“…In the solid state, both lithium propiolamidinates crystallize in the triclinic space group P-1 with one dimeric molecule in the unit cell. The bond lengths and bond angles are in good agreement with similar structures of amidinate ligands [48][49][50][51][52][53][54][55][56][57][58]. The N-C distances in the amidinate N-C-N unit are 1.321(2) and 1.330(2) Å in 1 and 1.3201 (13) …”

“…Full crystallographic data can be found in the Supplementary Information. The crystal structure determinations of Li[Ph-C≡C-C(N i Pr)2] THF (1) and Li[Ph-C≡C-C(NCy)2] THF (2) in both cases revealed the presence of a ladder-type dimeric structure, which is the most characteristic structural motif of most previously characterized lithium amidinates and guanidinates [48][49][50][51][52][53][54][55][56][57][58]. The dimers are centrosymmetric with the central Li2N2 ring being strictly planar.…”

Structural Investigation of New Lithium Amidinates and Guanidinates

“…A straightforward and generally applicable preparation of lithium amidinates involves the addition of lithium alkyls to N , N ′‐diorganocarbodiimides in a 1:1 molar ratio. Lithium guanidinates are accessible in a similar manner by adding lithium‐ N , N ‐dialkylamides to N , N ′‐diorganocarbodiimides . The structural chemistry of alkali metal (particularly lithium) amidinates and guanidinates is clearly dominated by ladder‐type dimers, although higher aggregates have also been reported , …”

“…Lithium guanidinates are accessible in a similar manner by adding lithium-N,N-dialkylamides to N,NЈ-diorganocarbodiimides. [27][28][29][30][31] The structural chemistry of alkali metal (particularly lithium) amidinates and guanidinates is clearly dominated by ladder-type dimers, [32][33][34][35][36][37][38][39] although higher aggregates have also been reported. [3,40] In the present contribution we report the synthesis and full characterization of a series of new and potentially useful lith-ARTICLE iPrN=C=NiPr with 1 equiv.…”

Hybrid amidinates and guanidinates of main group metals

“…Further transmetallation to targeted transition metal complexes provided only the titanium ones but in the attempts to prepare yttrium complexes were unsuccessful. Further possibility is to modify the central carbon atom, which is taking place in the cases of 2-(N,N-dimethylaminomethyl)phenyl group substituted amidinate (Figure 6 left) [37] synthesized by an addition of lithium compound to two different carbodiimides. In the case of Page 15 of 32 A c c e p t e d M a n u s c r i p t 15 involvement of the smaller organic substituents on the parent carbodiimide -isopropyl groups -the dimeric centrosymmetric structure of the respective lithium isobidentate aminoamidinate without connection of the pendant amino group is observed.…”