Synthesis And Structure Of Alkyne Silver Clusters With Ethynylphenyl Diphenylphosphine As Ligand

Silver acetylides have attracted continuous attention in recent years.In addition to their intrinsic and fundamental importance in structural and photophysical chemistry,their potential applications are significant,such as in organic transformation,catalysis,and material sciences and so on.The triple bond can interact with Ag(?)by a bond and ? bond consulting diversity of coordination between triple bond and Ag(?).In addition to,the existence of metallophilic Ag(?)-Ag(?)interactions makes diversity of silver clusters.Extensive efforts have resulted in the synthesis and structural characterization of many silver acetylides.However,unmodified silver acetylides usually aggregate to form organometallic polymers,which are not soluble and precipitate immediately upon formation.As a result,in the synthesis of these complexes,phosphine ligands,which have simple but strong Ag(?)-P coordination interactions,have been frequently used as capping ligands to confine the silver cluster to a certain size by preventing its uncontrolled and infinite growth.Ligand design therefore plays a critical role in the research of silver acetylides.In addition to simple ligands containing one ethynide or one phosphine binding site for Ag(I),alkynyl ligands that have two or more ethynide groups and also di-and triphosphine ligands have been explored for the construction of silver acetylides with various complicated structures largely due to the presence of additional coordination and bridging modes.However,silver acetylides reported so far in general present either discrete cluster structures or polymeric structures with small silver cluster building blocks.In order to get new silver acetylides,we are interested in combining the benefits of both ethynide and phosphine binding sites in one single ligand.The bifunctional ligand can use the ethynide part to create silver clusters and use the phosphine part to control the silver cluster size.Importantly,unlike using individual alkynyl and phosphine ligands,the assembly of both binding sites in one single ligand is expected to form silver acetylide frameworks through bridging Ag(?)-P-C6H4-4-C?C-Ag(?)linkages.Herein we synthesis of(4-ethynylphenyl)diphenyl phosphine,and we design and synthesis(3-ethynylphenyl)diphenyl phosphine by shortening the distance between ethynyl and phosphine.Upon deprotonation of the acetylene unit,the resulted bifunctional Ph2P-C6H4-4-C?C-(L1)ligand and Ph2P-C6H4-3-C?C-(L2)can interact with AgNO3 and AgCF3CO2 respectivly getting[AgLl]n and[AgL2]n.Reactions of[AgL1]n and AgCF3CO2 under different conditions gave four silver acetylides,including[Ag18L18(CF3COO)6(HCO3)4(DMF)4]n(1,DMF = dimethylformamide),[Ag20L18(CF3COO)12(DMF)6]n(2),[Ag17L16(CF3COO)9(HC03)2]n(3),and[Ag17L16(CF3COO)9.56(HCO3)1.44]n(4).[AgL2]n was dissolved in the MeOH solution directly,getting the silver acetylide Ag20L212(CF3COO)8(5).Crystallographic studies revealed that complex 1 crystallized in the triclinic space group P1 with a = 14.1252(9)A,b = 18.6012(12)A,c = 25.2137(17)A,? = 108.340(2)°,?= 95.386(2)°,?=95.535(2)°,V= 6204.6(7)A3,and Z = 1.Complex 2 crystallized in the monoclinic space group C2/c with a = 48.046(4)A,b=14.1860(10)A,c = 34.943(2)A,?=98.315(3)°,V = 23566(3)A3,and Z = 4.Complex 3 crystallized in the triclinic space group P 1 with a = 15.5690(7)A,b = 16.7707(8)A,c = 34.0810(16)A,?=93.4040(10)°,?= 100.3690(10)°,?= 94.8250(10)°,V = 8697.1(7)A3,and Z = 2.Complex 4 crystallized in the triclinic space group P 1 with a = 15.5396(6)A,b =16.7595(7)A,c = 34.0225(15)A,? = 93.8140(10)°,? = 100.1000(10)°,?=94.9770(10)°,V=8660.2(6)A3,and Z = 2.complex 5 crystallized in the triclinic space group P 1 with a = 20.2114(10)A,b = 20.6499(10)A,c = 34.7101(16)A,? =34.7101(16)°,?= 99.7600(10)°,?= 118.0390(10)°,V= 12447.6(10)A3,and Z=2.The presence of Ag(?)-C,Ag(?)-P and Ag(?)-Ag(?)bonding interactions makes complexes 1-4 represented that very rare examples of silver acetylide frameworks assembled using high-nuclearity silver cluster building blocks,which is rare reported.Complexes 1 and 2 have two-dimensional(2D)network structures,while complexes 3 and 4 have three-dimensional(3D)framework structures.Different with complexes 1-4,complex 5 is zero structure.