Crystalline metal (Li, Mg, Ca, Sr, Ba, Sn, Pb) complexes of the new chelating N,N′-dianionic [1,2-N(R)C_6H_4(CH _2NR)]~(2-) ligand (R = SiMe_3, CH _2Bu~t)

摘要

2-Aminomethylaniline was converted into the N,N′-bis(pivaloyl) (1) or -bis(trimethylsilyl) (2) derivative, using 2 Bu~tC(O)Cl or 2 Me _3SiCl (RCl), respectively, with 2 NEt_3, or for 2 from successively using 2 LiBu~n and 2 RCl. N,N′-Bis(neopentyl)-2- (aminomethyl)aniline (3) was prepared by LiAlH_4 reduction of 1. From 2 or 3 and 2 LiBu~n, the appropriate dilitiodiamide {2-[{N(Li)R}C _6H_4{CH_2N(Li)R}(L)]_2 (L absent, 4a; or L = THF, 4b) or the N,N′-bis(neopentyl) analogue (5) of 4a was prepared. Treatment of 4a with 2 Bu~tNC, 2 (2,6-Me_2C _6H_3NC) or 2 Bu~tCN (L′) furnished the corresponding adduct [2-N{Li(L′)R}C_6H_4{CH _2N(Li)R}] (4c, 4d or 4e, respectively), whereas 4b with 2 PhCN afforded [2-{N(Li)R}C_6H_4{CH_2C(Ph) = NLi(NCPh)}] (6). The dimeric bis(amido)stannylene [Sn{N(R)C_6H _4(CH_2NR)-1,2}]_2 (7) was obtained from 4a and [Sn(μ-Cl)NR_2]_2, while the N,N′-bis(neopentyl) analogue 8 of 7 was similarly derived from [Sn(μ-Cl)NR_2] _2 and 5. Reaction of two equivalents of the diamine 2 with Pb(NR _2)_2 yielded 9, the lead homologue of 7. Oxidative addition of sulfur to 7 led to the dimeric bis(diamido)tin sulfide 10. Treatment of 2 successively with 'MgBu_2' in C_5H_(12) and THF gave [Mg{N(R)C_6H_4(CH_2NR)}(THF)]_2 (11a), which by displacement of its THF by an equivalent portion of Bu~tCN or PhCN produced [Mg{N(R)C_6H_4(CH_2NR)}(CNR') _n] [R′ = Bu~t, n = 1 (11b); R′ = Ph, n = 2 (11c)]. The Ca (12), Sr (13) or Ba (14) analogues of the Mg compound 11a were isolated from 2 and either the appropriate compound M(NR_2) _2 (M = Ca, Sr, Ba), or successively 2 LiBu~n and 2 M(OTos)_2. The new compounds 1-14 were characterized by microanalysis (C, H, N; not for 1, 2, 3, 5), solution NMR spectra, ν_(max) (CN) (IR for 4c, 4d, 4e, 6, 11b, 11c), selected EI-MS peaks (for 1, 2, 3, 7, 8, 9, 10), and single crystal X-ray diffraction (for 4a, 4b, 11a).