Regioselective Cobalt(II) Catalyzed C-H Functionalization and [3 + 2] Annulation of -Arylguanidines with 1,3-Diynes.

8-Quinolinyl directed -arylguanidines were subjected to cobalt(II) catalyzed C-H functionalization/1,3-diyne annulation under mild conditions to afford 40 alkynylated indole guanidines in 34% to 92% yields. The scope of the substrates was explored. The reported procedure is mostly regioselective and tolerates various functional groups in the substrates.

Syntheses, structural, photophysical and theoretical studies of heteroleptic cycloplatinated guanidinate(1-) complexes bearing acetylacetonate and picolinate ancillary ligands.

Cycloplatination of symmetrical ,',''-triarylguanidines, (ArNH)C[double bond, length as m-dash]NAr with -[Pt(TFA)(S(O)Me)] in toluene afforded -[Pt(TAG)(TFA)(S(O)Me)] (TAG = triarylguanidinate(1-)-κ,κ; TFA = OC(O)CF; 6-9) in 75-82% yields. The reactions of 6-9 and the previously known -[Pt(TAG)X(S(O)Me)] (X = Cl (1) and TFA (2-5)) with acetylacetone (acacH) or 2-picolinic acid (picH) in the presence of a base afforded [Pt(TAG)(acac)] (acac = acetylacetonate-κ,'; 10-18) and [Pt(TAG)(pic)] (pic = 2-picolinate-κ,κ; 19) in high yields. The new complexes were characterised by analytical, IR and multinuclear NMR spectroscopies.

Influence of the Steric/Electronic Properties of -Aryl Substituents in Cycloplatinated Guanidinate(1-) Complexes on the Formation of Discrete Pt → Ag Complexes and One-Dimensional Coordination Polymer.

The reactions of cycloplatinated guanidinate(1-) complexes - with AgTFA (TFA = OC(O)CF) in 1:1 and 1:2 Pt/Ag molar ratios afforded complexes containing three types of PtAg skeletons (-, , and ), one 1D CP containing PtAg skeleton (), and a PtAg complex () in 91-95% (method 1), 73-82% (method 2) (-), and 54-79% (, , , and ) yields. The reactions of with 2,6-XylNC (2,6-Xyl = 2,6-MeCH) and 4-DMAP (4-dimethylaminopyridine) gave a neutral complex and an ionic complex , respectively. Molecular structures of 12 complexes were unambiguously determined by single-crystal X-ray diffraction.

Cobalt(II)-Catalyzed Directed C-H Functionalization/[3+2] Annulation of -Arylguanidines with Alkynes.

A family of ,'-diaryl-″-(quinolin-8-yl)guanidines were prepared by two methods, and these guanidines were subjected to Co(II)-catalyzed C-H functionalization/annulation with terminal and internal alkynes under mild conditions to afford a family of indole guanidines. Substrates with a range of electronic and steric properties were tolerated. The fluxional behavior of two guanidines and molecular structures of nine compounds are reported.

Reactions of Cycloplatinated Guanidine Complexes with Hg(OC(O)CF): Formation of a One-Dimensional Coordination Polymer Containing a PtHg(μ-S(O)Me-,) Repeating Unit versus a Discrete PtHg Complex.

Separate reactions of cycloplatinated 2-tolyl- and 2-anisylguanidine complexes, [Pt{κ(,)}(OC(O)CF)(S(O)Me)] ( and ), with Hg(OC(O)CF) in 1:0.5 and 1:1 molar ratios afforded the one-dimensional coordination polymer (1D CP) {[Pt{κ(,)}(OC(O)CF)]Hg}(μ-S(O)Me-,)·CH (·CH) as bright red crystals and the discrete tetrametallic complex [Pt{κ(,)}(μ-OC(O)CF)Hg-] () as yellow crystals in good yields. The two different products obtained in the aforementioned reactions are ascribed to the subtle differences in the N substituent of the guanidinate(1-) ligands in and .

Critical Role of Anions in Platinum(II) Precursors upon the Structural Motifs of Six-Membered Cycloplatinated ,',″-Triarylguanidines.

The reactions of -[Pt(OAc)(DMSO)] with 2 equiv of ,',″-triarylguanidines, [ArN=C(NHAr)], in toluene under reflux condition for 8 h afforded six-membered cycloplatinated guanidines, [Pt{κ(,)}(OAc){κ (ArN=C(NHAr))}] [ = symmetrical; Ar = 2-MeCH () and 2,4-MeCH ()], in 82 and 84% yields, respectively. The salt metathesis reaction of with 1 equiv of AgTFA in CHCl at room temperature (RT) afforded [Pt{κ(,)}(TFA){κ (ArN=C(NHAr))}] () in 94% yield. The reaction of -[Pt(TFA)(DMSO)] with 1 equiv of [ArN=C(NHAr)] in toluene under reflux condition for 8 h afforded six-membered cycloplatinated guanidines, [Pt{κ(,)}(TFA)(DMSO)] [Ar = 2-MeCH (), 4-MeCH (), 2,4-MeCH (), and 2-(MeO)CH ()], in ≥73% yields.

Dual role of acetate as a nucleophile and as an internal base in cycloplatination reaction of sym-N,N',N″-triarylguanidines.

Reaction of cis-[Cl(2)Pt(S(O)Me(2))(2)] with 1 equiv of sym-N,N',N″-triarylguanidines, ArN═C(NHAr)(2) (sym = symmetrical; Ar = 2-MeC(6)H(4) (LH(2)(2-tolyl)), 2-(MeO)C(6)H(4) (LH(2)(2-anisyl)), 4-MeC(6)H(4) (LH(2)(4-tolyl)), 2,5-Me(2)C(6)H(3) (LH(2)(2,5-xylyl)), and 2,6-Me(2)C(6)H(3) (LH(2)(2,6-xylyl))) in toluene under reflux condition for 3 h afforded cis- or trans-[Cl(2)Pt(S(O)Me(2))(ArN═C(NHAr)(2))] (Ar = 2-MeC(6)H(4) (1), 2-(MeO)C(6)H(4) (2), 4-MeC(6)H(4) (3), 2,5-Me(2)C(6)H(3) (4), and 2,6-Me(2)C(6)H(3) (5), respectively) in 83-96% yield. Reaction of cis-[Cl(2)Pt(S(O)Me(2))(2)] with 1 equiv of LH(2)(2-tolyl) and LH(2)(4-tolyl) in the presence of 1 equiv of NaOAc in methanol under reflux condition for 3 h afforded acetate-substituted products, cis-[(AcO)ClPt(S(O)Me(2))(ArN═C(NHAr)(2))] (Ar = 2-MeC(6)H(4) (6) and 4-MeC(6)H(4) (7)) in 83% and 84% yields, respectively. Reaction of cis-[Cl(2)Pt(S(O)Me(2))(2)] with 1 equiv of LH(2)(2-anisyl) and LH(2)(2-tolyl) in the presence of 1 equiv of NaOAc in methanol under reflux condition for 3 and 12 h afforded six-membered [C,N] platinacycles, [Pt{κ(2)(C,N)-C(6)H(3)R-3(NHC(NHAr)(═NAr))-2}Cl(S(O)Me(2))] (Ar = 2-RC(6)H(4); R = OMe (8) and Me (9)), in 92% and 79% yields, respectively.

Synthesis, reactivity studies, structural aspects, and solution behavior of half sandwich ruthenium(II) N,N',N''-triarylguanidinate complexes.

[(η(6)-C(10)H(14))RuCl(μ-Cl)](2) (η(6)-C(10)H(14) = η(6)-p-cymene) was subjected to a bridge-splitting reaction with N,N',N''-triarylguanidines, (ArNH)(2)C═NAr, in toluene at ambient temperature to afford [(η(6)-C(10)H(14))RuCl{κ(2)(N,N')((ArN)(2)C-N(H)Ar)}] (Ar = C(6)H(4)Me-4 (1), C(6)H(4)(OMe)-2 (2), C(6)H(4)Me-2 (3), and C(6)H(3)Me(2)-2,4 (4)) in high yield with a view aimed at understanding the influence of substituent(s) on the aryl rings of the guanidine upon the solid-state structure, solution behavior, and reactivity pattern of the products. Complexes 1-3 upon reaction with NaN(3) in ethanol at ambient temperature afforded [(η(6)-C(10)H(14))RuN(3){κ(2)(N,N')((ArN)(2)C-N(H)Ar)}] (Ar = C(6)H(4)Me-4 (5), C(6)H(4)(OMe)-2 (6), and C(6)H(4)Me-2 (7)) in high yield. [3 + 2] cycloaddition reaction of 5-7 with RO(O)C-C≡C-C(O)OR (R = Et (DEAD) and Me (DMAD)) (diethylacetylenedicarboxylate, DEAD; dimethylacetylenedicarboxylate, DMAD) in CH(2)Cl(2) at ambient temperature afforded [(η(6)-C(10)H(14))Ru{N(3)C(2)(C(O)OR)(2)}{κ(2)(N,N')((ArN)(2)C-N(H)Ar)}]·xH(2)O (x = 1, R = Et, Ar = C(6)H(4)Me-4 (8·H(2)O); x = 0, R = Me, Ar = C(6)H(4)(OMe)-2 (9), and C(6)H(4)Me-2 (10)) in moderate yield.

Factors dictating the nuclearity/aggregation and acetate coordination modes of lutidine-coordinated zinc(II) acetate complexes.

The reactions of Zn(OAc)(2).2H(2)O with various positional isomers of lutidine were explored with a view to understand the factors responsible for the nuclearity/aggregation and acetate coordination modes of the products. The reactions of Zn(OAc)(2).

Comparisons of phosphorus ligation properties in P(CH2NR)3P.

Bicyclic P(CH2NMe)3P was synthesized, and its reactions with MnO2, elemental sulfur, p-toluenesulfonyl azide, BH3.THF, and W(CO)5(THF) were shown to furnish a variety of products in which the PC3 and/or the PN3 phosphorus are oxidized/coordinated. In contrast, reactions of the previously known P(CH2NPh)3P with Mo(0) and Ru(II) precursors were shown to afford products in which only the PC3 phosphorus is coordinated.

Synthesis and photoelectron spectroscopic studies of N(CH2CH2NMe)3P=E (E = O, S, NH, CH2).

The synthesis and the crystal and molecular structure of N(CH(2)CH(2)NMe)(3)P=CH(2) is reported. The P-N(ax) distance is rather long in N(CH(2)CH(2)NMe)(3)P=CH(2). The ylide N(CH(2)CH(2)NMe)(3)P=CH(2) proved to be a stronger proton acceptor than proazaphosphatrane N(CH(2)CH(2)NMe)(3)P, since it was shown to deprotonate N(CH(2)CH(2)NMe)(3)PH(+).

An investigation of Staudinger reactions involving cis-1,3,5-triazidocyclohexane and tri(alkylamino)phosphines.

The reaction of 1,3,5-cis-triazidocyclohexane with the electron-rich tris(dialkylamino)phosphines P(NMe(2))(3) (1) and N(CH(2)CH(2)NMe)(3)P (2b) in acetonitrile for 3 h furnished the corresponding tris-phosphazides 1,3,5-cis-(R(3)PN(3))(3)C(6)H(9), 3a (R(3)P = 1) and 3b (R(3)P = 2b), in 90% and 92% yields, respectively. The same reaction with the relatively electron-poor tris(dialkylamino)phosphine MeC(CH(2)NMe)(3)P (4) for 2 days gave the tris-iminophosphorane, 1,3,5-cis-(R(3)PN)(3)C(6)H(9), 5a (R(3)P = 4), in 60% yield. Compound 3b is a thermally stable solid that did not lose dinitrogen when refluxed in toluene for 24 h or when heated as a neat sample at 100 degrees C /0.

Reactions of tris(amino)phosphines with arylsulfonyl azides: product dependency on tris(amino)phosphine structure.

The Staudinger reaction of N(CH2CH2NR)3P [R = Me (1), Pr (2)] with 1 equiv of N3SO2C6H4Me-4 gave the ionic phosphazides [N(CH2CH2NR)3PN][SO2C6H4Me-4] [R = Me (3), R = Pr (5a)], and the same reaction of 2 with N3SO2C6H2Me3-2,4,6 gave the corresponding aryl sulfinite 5b. On the other hand, the reaction of 1 with 0.5 equiv of N3SO2Ar (Ar = C6H4Me-4) furnished the novel ionic phosphazide [[N(CH2CH2NMe)3P]2(mu-N3)][SO2Ar] (6).

Oxidative Addition of Tetrachloro-1,2-benzoquinone to lambda(3)-Cyclotriphosphazanes. An Unusual Ring Contraction-Rearrangement.

The lambda(3)-cyclotriphosphazanes, [EtNP(OR)](3) [R = 2,6-Me(2)C(6)H(3) (1), 4-BrC(6)H(4) (2), or CH(2)CF(3)(3)], on treatment with tetrachloro-1,2-benzoquinone (TCB) give the lambda(5)-cyclodiphosphazanes, [EtNP(O(2)C(6)Cl(4))(OR)][EtNP(O(2)C(6)Cl(4)){N(Et)P(OR)(2)}] (5-7) by an unusual ring contraction-rearrangement. The reaction of the mixed substituent lambda(3)-cyclotriphosphazane, [(EtN)(3)P(3)(OR)(2)(OR')] [R = 2,6-Me(2)C(6)H(3), R' = 4-BrC(6)H(4)] (4), with TCB gives the lambda(5)-cyclodiphosphazane, [EtNP(O(2)C(6)Cl(4))(OR')][EtNP(O(2)C(6)Cl(4)){N(Et)P(OR)(2)}] (8), in which 4-bromophenoxide resides on one of the ring phosphorus atoms. The lambda(3)-bicyclic tetraphosphapentazane, (EtN)(5)P(4)(OPh)(2), on treatment with TCB undergoes a double ring contraction-rearrangement to give the lambda(5)-cyclodiphosphazane, (EtN)[(EtN)(2)P(2)(O(2)C(6)Cl(4))(2)(OPh)](2) (9).