The Main Group Macrocycle [{(PCH2CH2PAlMe2)2}4]⋅4 [AlMe3]

Abstract

Four P4 chains link eight aluminum centers in the [P16Al8] macrocycle [{(PCH2CH2PAlMe2)2}4]⋅4 [AlMe3] (1), which has a unique macrocyclic structure comprised solely of main group elements. Compound 1 is produced by the reaction of [AlMe3] (see scheme) with the catalytically produced organotetraphosphane (PCH2CH2PH)2 (2).

Dehydrogenative Bond-Forming Catalysis Involving Phosphines

“…Bicycle 11 reacted with Lewis acid GaMe 3 to give a meta-stable 2:1 adduct (PCH 2 CH 2 PH) 2 (GaMe 3 ) 2 , which was characterized by NMR spectroscopy (Scheme 3). The PhP PPh PhHP PHPh reaction of 11 and AlMe 3 was slow, but gave a tetrameric product linked by AlMe 2 groups, [(CH 2 CH 2 P 2 Al Me 2 ) 2 ] 4 ·4AlMe 3 , which was structurally characterized [63]. Further dehydrocoupling of 1,2-bis(phenylphosphino) benzene with anionic zirconocene hydride 1 afforded a unique 16-member phosphacycle (C 6 H 4 P 2 ) 8 (13), which was structurally characterized (eq.…”

“…Reaction of 1 or 5 with 1,2-bis (phenylphosphino)ethane or 1,2-bis(phenylphosphino)benzene gave bicyclic complexes (PCH 2 CH 2 PH) 2 (11) and (PC 6 H 4 PH) 2 (12) with intercalated phosphorus atoms (Scheme 2) [60,63,64]. These two dimers are each precursors to more complex structures.…”

Selective Dehydrocoupling of Phosphines by Triamidoamine Zirconium Catalysts

“…Two families of rhodium catalysts have been reported, and in dehydrocoupling reactions of primary phosphines, the diphosphine products are produced. , Early transition-metal catalysts, particularly those of the group 4 metals, are tremendously promising in phosphine dehydrocoupling due to their high reactivity and low cost. − However, the observed selectivity has been poor. Reported catalysts form only mixtures of (RPH) 2 and (PR) n ( n = 4, 5, or 6) unless the substrate is a bulky 2,4,6-substituted arylphosphine 4e. To make this catalysis viable for synthetic applications, new metal complexes that improve on the current selectivity are required.…”

Multiple Cycloaddition Reactions of Ketones with a β‐Diketiminate Al Compound

“…Literature reports on aluminium‐containing ring systems by using nitrile insertion into AlN bonds are available 5. Synthesis of macrocyclic AlP compounds were reported by Stephan and co‐workers6 and by Hänisch and co‐workers7 using alkyl aluminium compounds as reactants. Macrocyclic binucleating β‐diketiminate ligands were utilized by the Holland group for preparing aluminium complexes 8.…”