Lithium and Zinc Complexes of C‐ and N‐Functionalized (2‐Pyridylmethyl)amines

Abstract

The addition reaction of benzophenone with lithium (2‐pyridylmethyl)(tert‐butyldimethylsilyl)amide yields dimeric1‐lithoxy‐1,1‐diphenyl‐2‐(2‐pyridyl)‐2‐(trialkylsilylamino)ethane (1) with formation of a C–C bond. C‐Functionalized 2‐(pyridylmethyl)amines are accessible via the reaction of N‐(2‐pyridylmethylidene)phenylamine with diethylmalonate giving 2,2‐bis(ethoxycarbonyl)‐1‐(phenylamino)‐1‐(2‐pyridyl)ethane (2) which eliminates aniline upon heating yielding diethyl 2‐(2‐pyridylmethylidene)malonate (3). The addition of piperidine leads to the formation of the Michael type adduct 2,2‐bis(ethoxycarbonyl)‐1‐piperidyl‐1‐(2‐pyridyl)ethane (4) which can be deprotonated with metal‐organic reagents such as Zn[N(SiMe3)2]2, Zn[CH(SiMe3)2]2, LiN(SiMe3)2, and NaN(SiMe3)2 leading to 2,2‐bis(ethoxycarbonyl)‐1‐piperidyl‐1‐(2‐pyridyl)ethane‐2‐yl complexes of zinc (5 and 6), lithium (7), and sodium (8). N‐Functionalization can be achieved via the reaction of (2‐pyridylmethyl)(trialkylsilyl)amine with benzoyl chloride giving N‐(2‐pyridylmethyl)benzoylamine (9). Lithiation and subsequent salt metathesis reaction with another equivalent of benzoyl chloride yields N‐(2‐pyridylmethyl)dibenzoylamine (10). The addition reaction of ZnCl2 with N‐(2‐pyridylmethyl)(diphenylmethylidene)amine (11) forms colorless crystalline [(Py–CH2N=CPh2)ZnCl2] (12). The addition of benzoyl chloride leads to N‐(diphenylchloromethyl)‐N‐(2‐pyridylmethyl)benzoylamine (13). Addition of ZnCl2 leads to the formation of solvent‐separated [(2‐pyridylmethyl)(benzoylamino)diphenylcarbonium] [(tetrahydrofuran)trichlorozincate] (14). The X‐ray crystal structures of 1, 4 to 7, 9, 12, and 14 are discussed.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Synthesis, characterization and cytotoxicity of gold(III) complexes with deprotonated pyridyl carboxamide

“…The ligands L1 , L2 , L3 , L4 , L5 , L6 (as shown in Fig. ) were prepared following reported procedures . Their structure and purity were established by comparing their melting points, IR and NMR data with those reported in the literature.…”

“…Ligands L1 , L2 , L3 , L4 , L5 , L6 were prepared as described in the literature . Gold(III) complexes were prepared by the reaction of pyridyl carboxamides with K[AuCl 4 ]·H 2 O in a mixture of C 2 H 5 OH/H 2 O (v/v, 1:1).…”

2-(Benzoylaminomethyl)pyridinium chloride

“…For general background, see: Westerhausen et al (2001Westerhausen et al ( , 2002. For related structures, see: Koch et al (2008); Prostota et al (2004).…”

“…In the past, metallated (2-pyridylmethyl)(trialkysilyl)amines were used for zinc-mediated oxidative C-C coupling reactions yielding [1,2-dipyridyl-1,2-bis(triisopropylsilylamido)ethane] bis(methylzinc) (Westerhausen et al 2001 and2002). The reaction of (2-pyridylmethyl)(tert-butyldimethylsilyl)amine and benzoyl chloride in toluene quantitatively yields N-(2-pyridylmethyl)benzoylamine ((1)) (Koch et al 2008). Treatment of (1) with benzoyl chloride after deprotonation with butyllithium gives N-(2-pyridylmethyl)dibenzoylamine with rather poor yields.…”

Accessing 1,2‐Substituted Cyclobutanes through 1,2‐Azaborine Photoisomerization

“…Thea ddition of pinacol then led to BÀNb ond cleavage and displacement of tert-amyl alcohol. Mindful that beyond this point the N-silyl group would likely be incompatible with many reaction conditions, its direct conversion [14] to am ore robust amide functionality was simultaneously achieved by the co-addition of benzoyl chloride.S ingle-crystal X-ray diffraction analysis [15] of the resulting benzamidocyclobutyl boronic ester (5)c onfirmed the molecule had retained the cis relative stereochemistry of the nitrogen and boron groups originally generated by the diastereoselective photoisomerization of 2.…”