Pulmonary Embolism after Liposuction Totally by Tumescent Local Anesthesia in a Patient with Large Uterine Fibroids.

A fatal pulmonary embolism occurred in a 43-year-old black woman after tumescent liposuction totally by local anesthesia. An autopsy revealed large uterine fibroids, peri-uterine vascular thrombi, and a large saddle pulmonary embolism. Large uterine fibroids are a risk factor for postsurgical venous thromboembolism. Fatal outcomes after tumescent liposuction totally by local anesthesia are exceedingly rare.

In defence of oxidation states.

In this Perspective, some of the criticisms which have been made concerning the use of oxidation states are addressed, particularly in the context of the teaching of inorganic chemistry. The Oxidation State method and the Covalent Bond Classification method are compared and contrasted, and it is concluded that while each method has its strengths and weaknesses, both are important in teaching and it should be recognized that no single model or method is appropriate in all circumstances.

Reply to the 'Comment on "In Defence of Oxidation States"' by J. C. Green, Dalton Transactions, 2022, 51, DOI: 10.1039/D1DT02930D.

We reiterate and reinforce some of the points concerning oxidation states and the Covalent Bond Classification method we made in the Perspective article entitled 'In Defence of Oxidation States' including a brief discussion of the relative merits of the terms 'metathesis' and 'redox' when considering addition across a metal-metal bond.

A polycyclic borazine radical cation: [1,2-B2{1,2-(MeN)2C6H4}2]˙(+).

The radical cation [1,2-B2{1,2-(MeN)2C6H4}2]˙(+) has been synthesised and its structure and bonding have been probed using a combination of X-ray crystallography, EPR spectroscopy and DFT calculations which show that it represents a new type of radical centred primarily on two N-heterocyclic units joined by a B2 linker but with only a minor contribution from boron-based orbitals.

Diborane(4) compounds with bidentate diamino groups.

The reaction between B(2)(NMe(2))(4) and 1,2-(NH(2))(2)-4-Bu(t)C(6)H(3) affords the diborane(4) compound 1,2-B(2){1,2-(NH)(2)-4-Bu(t)C(6)H(3)}(2) as the exclusive product whilst the reaction between rac-1,2-(NH(2))(2)C(6)H(10) and B(2)(NMe(2))(4) also affords only the 1,2-isomer, i.e. 1,2-B(2){1,2-(NH)(2)C(6)H(10)}(2), which is shown to be the more stable isomer by computational methods. The previously reported compounds 1,1-B(2){1,2-(NH)(2)C(6)H(4)}(2) and 1,2-B(2){1,2-(NH)(2)C(6)H(4)}(2) both react with four equivalents of Bu(n)Li to give what are presumed to be tetra-anions which react further with MeI, SnClMe(3) or SnClPh(3) to give the tetrasubstituted products 1,1-B(2){1,2-(NMe)(2)C(6)H(4)}(2), 1,1-B(2){1,2-(NSnMe(3))(2)C(6)H(4)}(2) and 1,2-B(2){1,2-(NSnPh(3))(2)C(6)H(4)}(2) respectively. The compound 1,1-B(2){1,8-(NH)(2)C(10)H(6)}(2) has also been prepared from the reaction between B(2)(NMe(2))(4) and 1,8-diaminonaphthalene. Lithiation and subsequent reaction with SnClMe(3), SnCl(2)Me(2) or SnCl(2)Ph(2) affords 1,1-B(2){1,8-(NSnMe(3))(2)C(10)H(6)}(2), 1,1-B(2){1,8-(N(2)-µ-SnMe(2))C(10)H(6)}(2) and 1,1-B(2){1,8-(N(2)-µ-SnPh(2))C(10)H(6)}(2) respectively. All new compounds have been characterised by X-ray crystallography.

A variable-temperature study of 1,2-bis(dimethylamino)-1,2-bis(2,6-dimethylanilino)diborane.

The title compound, C(20)H(32)B(2)N(4), is monoclinic at ambient temperature but triclinic (pseudo-monoclinic) below 150 K. The structures of the two phases, determined at 200 and 120 K, respectively, are very similar, the molecular symmetry being crystallographic C(2) and approximate (local) C(2), respectively. There is significant π conjugation within each N-B-N moiety, but none between them or between the N-B-N and arene moieties.

New polycyclic borazine species.

The new polycyclic borazines B(2){1,2-N(2)C(6)H(4)}(2){B(2)(NMe(2))(2)}(2), B(2){1,8-N(2)naph}(2){B(2)(NMe(2))(2)}(2) and B(2)(NPh)(4){B(2)(NMe(2))(2)}(2) have been prepared from diborate(4) anions and two equivalents of B(2)Cl(2)(NMe(2))(2) and have been structurally characterised. Aspects of their structure and bonding are discussed and comparison made with corresponding polycyclic aromatic hydrocarbons.

Synthesis and characterisation of the persistent radical [BCl2(bipy)]*.

The persistent radical, [BCl(2)(bipy)](*) (bipy = 2,2'-bipyridyl), has been prepared and characterised by X-ray crystallography, ESR and DFT calculations. The structure is compared with that of the cation, [BCl(2)(bipy)](+).

Boron-nitrogen analogues of the fluorenyl anion.

The synthesis and structural characterisation of [BPh(bipy)] and [BCl(bipy)] are described both of which contain a direduced bipy ligand (bipy = 2,2'-bipyridyl) and are analogues of the fluorenyl anion; DFT calculations highlight differences in the electronic structure of both species compared to the fluorenyl anion.

Unusual chalcogen-boron ring compounds: the gas-phase structures of 1,4-B4S2(NMe2)4 and related molecules.

The structure of 1,4-B4S2(NMe2)4 has been determined by gas-phase electron diffraction and quantum chemical calculations and is compared with the known solid-state structure. While these structures are similar, with a twisted ring geometry [the dihedral angle S-B-B-S from electron diffraction is 75.4(16) degrees], they are strikingly different to the solid-state structure of 1,4-B4O2(OH)4, which is planar. Using quantum chemical calculations, the combinations of O or S in the ring and OH or NMe2 as the substituent have been studied and it has been shown that there are two separate causes of the twisted ring. Since the calculated (and observed) structure of 1,4-B4O2(OH)4 is planar but that of 1,4-B4S2(OH)4 is twisted, it is concluded that the inclusion of sulfur in the ring twists the structure by approximately 40 degrees. By comparing the structures of 1,4-B4S2(OH)4 and 1,4-B4S2(NMe2)4 it has been determined that the twist caused by the NMe2 groups is around 30 degrees.

A simple entry into nido-C2B10 clusters: HCl promoted cleavage of the C-C bond in ortho-carboranyl diphosphines.

Treatment of the diphosphines ortho-B10H10C(P(t)Bu2)C(PR2) (R = Et, Cy, Ph) with HCl gives the zwitterionic, nido-12-vertex species B10H10C(PH(t)Bu2)C(PClR2); these reactions are reversed by the addition of NEt3.

A new cyclic borazine species B(8)(NH)(4)(NMe(2))(8) containing a twelve-membered B(8)N(4) ring.

The reaction between B(2)(NMe(2))(4) and two equivalents of [NH(4)][PF(6)] in thf at room temperature affords the new cyclic borazine B(8)(NH)(4)(NMe(2))(8) containing a non-planar twelve-membered ring with alternating B(2)(NMe(2))(2) and NH units.

Synthesis and reactivity of dichloroboryl complexes of platinum(II).

The reaction between [Pt(nbe)3] (nbe=norbornene), two equivalents of the phosphines PPh3, PMePh2 or PMe2Ph and 1 equivalent of BCl3 affords the platinum dichloroboryl species [PtCl(BCl2)(PPh3)2], [PtCl(BCl2)(PMePh2)2] and [PtCl(BCl2)(PMe2Ph)2]. All three complexes were characterised by X-ray crystallography and reveal that the boryl group lies trans to the chloride. With PMe3 as the phosphine, the complex [PtCl(BCl2)(PMe3)2] is isolated in high yield as a white crystalline powder although crystals suitable for X-ray crystallography were not obtained. Crystals were obtained of a product shown by X-ray crystallography to be the unusual dinuclear species [Pt2(BCl2)2(PMe3)4(micro-Cl)][BCl4] which reveals an arrangement in which two square planar platinum(II) centres are linked by a single bridging chloride which is trans to a BCl2 group on each platinum centre. The reaction of [PtCl(BCl2)(PMe3)2] with NEt3 or pyridine (py) affords the adducts [PtCl{BCl2(NEt3)}(PMe3)2] and [PtCl{BCl2(py)}(PMe3)2], respectively, both characterised spectroscopically. The reaction between [PtCl(BCl2)(PMe3)2] and either 4 equivalents of NHEt2 or piperidine (pipH) results in the mono-substituted boryl species [PtCl{BCl(NEt2)}(PMe3)2] and [PtCl{BCl(pip)}(PMe3)2], respectively, the former characterised by X-ray crystallography. Treatment of either [PtCl(BCl2)(PMe3)2] (in the presence of excess NEt3) or [PtCl{BCl(NEt2)}(PMe3)2] with catechol affords the B(cat) (cat=catecholate) derivative [PtCl{B(cat)}(PMe3)2] which is also formed in the reaction between [Pt(PMe3)4] and ClB(cat) and also from the slow decomposition of [Pt{B(cat)}2(PMe3)2] in dichloromethane over a period of months. The compound [Pt{B(cat)}2(PMe3)2] was prepared from the reaction between [Pt(PMe3)4] and B2(cat)2.

Synthesis and reactivity of cobalt boryl complexes.

The reaction between [Co(PMe3)4] and B2(4-Mecat)2 (4-Mecat = 1,2-O2-4-MeC6H3) or between [Co(PMe2Ph)4] and B2(cat)2 (cat = 1,2-O2C6H4) affords the paramagnetic Co(II) bisboryl complexes [Co(PMe3)3[B(4-Mecat)]2] and [Co(PMe2Ph)3{B(cat)]2] respectively, both of which have been structurally characterised. ESR data and preliminary diboration and boryl transfer reactivity studies are also presented. The reaction between [CoMe(PMe3)4] and B2(cat)2 affords the Co(I) monoboryl complex [Co(PMe3)4[B(cat)]].

Primary amido substituted diborane4 compounds and imidodiborate4 anions.

Treatment of the diborane(4) compound B(2)(NMe(2))(4) with aniline or 2,6-dimethylaniline results in the primary amido compounds B(2)(NHR)(4)(R = Ph, 2,6-Me(2)C(6)H(3)); subsequent treatment with n-BuLi in toluene in each case affords the first examples of anionic imidodiborates namely Li(4)(thf)(6)B(2)(NPh)(4) and Li(4)(thf)(4)B(2)(N-2,6-Me(2)C(6)H(3))(4); all complexes have been characterised crystallographically.

The structures of higher boron halides B8X12(X = F, Cl, Br and I) by gas-phase electron diffraction and ab initio calculations.

The structure of B8F12 has been shown by gas electron diffraction and computational methods (up to MP2/6-31+G*) to have the same highly asymmetric form observed in crystalline phases. The structure can be regarded as derived from a central B2 group, bridged by two BF2 groups to give a central B4 core that is folded, not planar, and with a very short bond [164.3 pm calculated, 164.2(19) pm experimental] along the fold line. There are also four terminal BF2 groups. One of the other four bonds in the core is consistently 20-30 pm longer than the others. This asymmetry has been attributed to many intra-molecular B...F interactions, particularly those between core boron atoms and fluorines of the terminal BF2 groups. Calculations for the chloro analogue lead to a structure similar to that for B8F12, but with the long core bond extended so that one of the bridging BCl2 groups may now be regarded as terminal. With bromine as the halogen the structure changes again, with one bromine atom taking up a bridging position. With iodine, this process continues further, and there are three bridging iodine atoms. However, in this case this is not the lowest energy structure, and instead a loosely associated dimer of B4I6 is preferred. In all these cases, and particularly with the heavier halogens, there are huge differences between the results obtained with different computational methods.

Structural analysis of five-coordinate transition metal boryl complexes with different d-electron configurations.

The site preference of boryl ligands in five-coordinate transition metal boryl complexes has been investigated with the aid of density functional theory calculations. The preferred site for a boryl ligand depends on the electron count of the complex under consideration. Our studies show that the very strong sigma-donating boryl ligands choose to occupy coordination sites such that those orbitals accommodating metal d electrons have minimal metal-boryl sigma-antibonding character.

Chlorobis(triphenylphosphine)nickel(I).

Crystals of the title compound, [NiCl(C(18)H(15)P)(2)], contain one molecule per asymmetric unit with no short intermolecular interactions. This is noteworthy since previous studies have reported that the formally 15-electron species oligomerizes in the solid state. The nickel(I) centre has a distorted trigonal-planar coordination geometry, the origin of which is suggested to be electronic in nature.