Nana Xin

: An efficient triflic anhydride promoted phosphorylation of ketone was disclosed, and vinylphosphorus compounds were prepared under solvent- and metal-free conditions. Both aryl and alkyl ketones could perform smoothly to give vinyl phosphonates in high to excellent yields. In addition, the reaction was easy to carry out and easy to scale up. Mechanistic studies suggested that this transformation might involve nucleophilic vinylic substitution or a nucleophilic addition-elimination mechanism.

An addition of H-phosphonates to aryl alkynes was realized under solvent- and metal-free conditions, affording Markovnikov-selective α-vinylphosphonates in moderate to good yields. A wide range of aryl alkynes could be applied for the reaction. A tentative mechanism of addition–substitution was proposed based on in situ ³¹P {¹H} NMR studies.

The binuclear- and mononuclear-copper complexes based on pyrazole-3-carboxylic acid (H₂pca) ligand: Cu₂(pca)₂(H₂O)₆·2H₂O (1) and Cu(Hpca)₂(H₂O)₂·2H₂O (2), have been controllable synthesized and fully characterized by single crystal X-ray diffraction (SXRD), thermal gravity analysis (TGA), powder X-ray diffraction (PXRD) and elemental analyses. Single-crystal X-ray structure analysis revealed that complex 1 displayed two Cu²⁺ cations and two pca^2– unit; however, complex 2 possessed one Cu²⁺ cation and two Hpca^– anion. Interestingly, complexes 1–2 can be achieved by tuning pH and the different copper salts using the H₂pca as staring materials. Moreover, the 3D supramolecular frameworks of complex 1 are formed by the tetrahedral water clusters, which composed by the three coordination water molecules and one lattice water molecular in the asymmetrical unit. For complex 2, the three dimensional frameworks are formed by the intermolecular O–H···O and N–H···O hydrogen bonding interactions. Notably, two complexes are further used as catalysts in the selective oxidation of benzylic sp ³ C–H bonds to produce ketones using t-butylhydroperoxide (TBHP) as the oxidant and they exhibit excellent heterogeneous catalytic performance (Conv. up to 99.6%, Sele. up to 99.4%).

One novel organic–inorganic Zn-Sm heterometallic hybrids materials, {Na(H₂O)₄ [SmZn₁₆(picha)₁₆(Py)₈](OTf) · 4MeOH · 12H₂O} (1), [H₂picha = picoline hydroxamic acid, Py = pyridine, HOTf = trifluoromethanesulfonic acid] was easily achieved and fully characterized by single crystal X-ray diffraction analyses (SCXRD), elemental analyses, infrared spectra (IR) and thermal gravimetric analysis (TGA). SCXRD revealed that complex 1 consisted of two concave 12-metallacrowns-4 units that sandwich an eight-coordinate Sm³⁺ central metal, and the sandwich structure is enclosed in a cavity of a 24-metallacrowns-8 unit. In the supramolecular structure of complex 1, the one-dimensional chain is formed by the weak intermolecular weak actions of C–H...O bonds. Importantly, complex 1 exhibit efficient heterogeneous catalytic performance (conversion: up to 96.3% and selectivity: up to 98.7%) in the catalytic conversion of CO₂ to cyclic carbonate.

A series of bibenzo[b][1,4]thiazines with various functional groups has been synthesized by a free-radical condensation reaction. Bibenzo[b][1,4]thiazines were obtained in moderate to good yield (up to 85%) through a one-step reaction of readily available 2,2′-dithiodianiline and methyl aryl ketones with AIBN as radical initiator in HOAc. Bibenzo[b][1,4]thiazines exhibit diversiform solid-state packing.

Hydrophosphorylated fullerene derivatives were readily prepared in one step by treating C₆₀ with Ph₃– _n PCl _n (n = 1–3) and ROH (R = H, alkyl). The one-pot reaction could be performed under mild conditions with moderate to good yields. Dichlorophenylphosphine and alcohols exhibited unexpected reactivity towards C₆₀. A possible reaction mechanism involving the formation of P(III)–OH in situ was proposed to explain the experimental results.

A novel metal-free one-pot protocol for the effective and efficient synthesis of 3-phosphinoylbenzofurans via a phospha-Michael addition/cyclization of H-phosphine oxides and in situ generated ortho-quinone methides is described. Based on the expeditious construction of C(sp²)–P bonds, asymmetric synthesis of optically pure 3-phosphinoylbenzofurans containing chiral P-stereogenic center has also been probed by using chiral R_P-(−)-menthyl phenylphosphine oxide.

An open‐cage C₆₀ derivative 9 with anilino, hemiketal, and lactone moieties on the edge of the opening was prepared through a fullerene‐mixed peroxide procedure. Key steps include decarbonylation, intramolecular Friedel–Crafts reaction and oxetane ring opening rearrangement. The open‐cage compound 9 readily reacts with various metal salts. A nickel complex was obtained by treating 9 with NiCl₂ at r.t. followed by purification on a silica gel column. Single‐crystal X‐ray diffraction analysis showed that the nickel ion is coordinated to two ligands with an octahedral geometry.

Aromatic methyl ketones and cyclic asymmetric ketones underwent hydrophosphorylation with P-stereogenic H–P species in the presence of potassium carbonate to produce P,C-stereogenic tertiary α-hydroxyl phosphinates in excellent yields with up to 99 : 1 dr. The diastereoselectivity was induced by a reversible conversion of less stable stereomer of product to that of a more stable one via an equilibrium, which was confirmed by aldehyde/ketone exchanging reaction. Toward the exchange, aliphatic or aldehyde carbonyl were more active than aromatic or ketone carbonyls, respectively. The stability difference between the two diastereomers was controlled by the sizes of substituents linking to phosphorus or α-carbon.