Diorganodiselenides and zinc(ii) organoselenolates containing (imino)aryl groups of type 2-(RNCH)C6H4

Abstract

Several new diorganodiselenides containing (imino)aryl groups, [2-(RN[double bond, length as m-dash]CH)C(6)H(4)](2)Se(2) [R = Me(2)NCH(2)CH(2) (4), O(CH(2)CH(2))(2)NCH(2)CH(2) (5), PhCH(2) (6), 2',6'-(i)Pr(2)C(6)H(3) (7)] were obtained by reacting [2-{(O)CH}C(6)H(4)](2)Se(2) (3) with RNH(2). Treatment of the diselenides 6 and 7 with stoichiometric amounts of K-selectride or Na resulted in isolation of the selenolates K[SeC(6)H(4)(CH[double bond, length as m-dash]NCH(2)Ph)-2] (9) and Na[SeC(6)H(4)(CH[double bond, length as m-dash]NC(6)H(3)(i)Pr(2)-2',6')-2] (10), respectively. The reaction of potassium selenolates with anhydrous ZnCl(2) (2:1 molar ratio) gave Zn[SeC(6)H(4)(CH=NCH(2)Ph)-2](2) (11) and Zn[SeC(6)H(4)(CH[double bond, length as m-dash]NC(6)H(3)(i)Pr(2)-2',6')-2](2) (12). When the dark green solution obtained from diselenide 7 and an excess of Na (after removal of the unreacted metal) was reacted with anhydrous ZnCl(2) a carbon-carbon coupling reaction occurred and the 9,10-(2',6'-(i)Pr(2)C(6)H(3)NH)(2)C(14)H(10) (8) species was obtained. The compounds were investigated in solution by multinuclear NMR ((1)H, (13)C, (77)Se, including 2D and variable temperature experiments) and by mass spectrometry. The molecular structures of 6, 8, 11 and 12 were established by single-crystal X-ray diffraction. All compounds are monomeric in the solid state. In the diselenide 6 the (imino)aryl group acts as a (C,N)-ligand resulting in a distorted T-shaped coordination geometry of type (C,N)SeX (X = Se). For the zinc complexes 11 and 12 the (Se,N) chelate pattern of the selenolato ligands results in tetrahedral Zn(Se,N)(2) cores.

Lithium–Bromide Exchange versus Nucleophilic Addition of Schiff's base: Unprecedented Tandem Cyclisation Pathways

“…The closest literature example is a serendipitous result arising from diorganodiselenides, containing an iminoaryl group, which in the presence of sodium metal and zinc chloride results in the formation of a cis ‐9,10‐bis(arylamino)‐9,10‐dihydroanthracene species. This is believed to proceed via a radical intermediate . A similar result, originating from an ortho ‐bromo‐substituted aryl imine, is the formation of a titanium 9,10‐dihydrophenanthrenediamide accessed via ortho ‐lithiation and subsequent transmetallation with TiCl 4 .…”

“…This is believed to proceed via ar adicali ntermediate. [20] As imilar result, originating from an ortho-bromo-substituted aryl imine, is the formation of at itanium9 ,10-dihydrophenanthrenediamide accessed via ortho-lithiation and subsequent transmetallation with TiCl 4 . [8] In our system, no other metal salt is present for metathesis to occur andh ence the reactive lithiated species couplesw ith itself via 1,2-nucleophilic addition.…”

Organoselenium compounds containing pyrazole or phenylthiazole groups: Synthesis, structure, tin(IV) complexes and antiproliferative activity

“…Our interest has been focused during the last few years on the synthesis and structural characterization of organoselenium compounds and main group organometallic species with aromatic organic groups bearing pendant arms with nitrogen donor atoms capable of N→E intramolecular interactions, e.g. 2‐(R 2 NCH 2 )C 6 H 4 (R = Me, Et, Pr i , E = Se; R = Me, E = Sn), 2‐{Z(CH 2 CH 2 ) 2 NCH 2 }C 6 H 4 (Z = O, NMe, E = Se) or 2‐(RN═CH)C 6 H 4 (R = Me 2 NCH 2 CH 2 , O(CH 2 CH 2 ) 2 NCH 2 CH 2 , PhCH 2 , 2,6‐iPr 2 C 6 H 4 , E = Se). We recently reported the heteroleptic diorganoselenium(II) compounds [2‐(R 2 NCH 2 )C 6 H 4 ][(3,5‐dmpz)CH 2 CH 2 ]Se (R = Me, Et, dmpz = dimethylpyrazole), [2‐(Me 2 NCH 2 )C 6 H 4 ](pzCH 2 CH 2 )Se (pz = pyrazole) and [2‐(Me 2 NCH 2 )C 6 H 4 ](PhtzCH 2 )Se (Phtz = phenylthiazole) .…”

Synthesis and X‐ray Structural Characterization of Di‐p‐aminobenzenediselenide [p‐H2NC6H4Se]2 and its Mercury(II) Derivatives

“…The reaction of the alkali metal selenolates K[SeC 6 H 4 (CH=NCH 2 Ph)‐2] and Na[SeC 6 H 4 (CH=NC 6 H 3 ‐ i Pr2–2′,6′)‐2], which contained (imino)aryl groups, with anhydrous ZnCl 2 (in a 2:1 molar ratio) gave Zn[SeC 6 H 4 (CH=NCH 2 Ph)‐2] 2 and Zn[SeC 6 H 4 (CH=NC 6 H 3 ‐ i Pr2–2′,6′)‐2] 2 23. The solid‐state monomeric structures of the complexes were stabilized by intramolecular N→Zn interactions.…”