Binary adducts

Attempts have been made to systematize the nomenclature, and Herbstein, in his major work Crystalline Molecular Complexes and Compounds, gives a classification scheme for binary adducts made up of compounds A and B, which depend on the dominance of the A- A, B- B, and A- B interactions. 

The relevant terminology has been in constant flux moving from addition compounds (Timmermans phrase) to (part of) supramolecular chemistry. Herbstein [2005] uses the generic term binary adducts and classifies them into inclusion complexes and molecular compounds, using as the criterion for separating com-... 

As Herbstein remarks, undoubtedly many binary adducts will be found to straddle classificatory boundaries (10), to which we may add because there are too many classification criteria which will be valued differently in different contexts, thus supporting Dupre s [1993] proposals to allow promiscuous natural kinds. Although modern crystallography has disclosed a lot of structural information hidden behind the dot in formulas such as H2SO4 4H2O, it seems that every new detailed investigation uncovers new possibilities for arrangement, as well as new stable and metastable phases. 

Finally, some methods are also based on the selective formation of binary adducts, MtAMcfl (where Mt means metalloid and Me metal, usually, copper), whose electrode transformations are correlated with the quantity of the respective metalloid. ... 

Reactions in chloroaluminate(III) salts and other related binary salts often proceed smoothly to give products. However, it should be noted that these salts are water-sensitive and must be handled under dry conditions. They react with water to give hydrated aluminium(III) ionic species and HCl. When a reactant or product contains a heteroatomic functional group, such as a ketone, a strong ketone/alumini-um(III) chloride adduct is formed. In these cases, this adduct can be difficult to separate from the ionic liquid at the end of a reaction. The isolation of the product often... 

Later on, this concept was extended to precursors containing both elements of the desired material already connected by a chemical bond in a single molecule. Such precursors are mainly referred to as single source precursors. Their potential application for the deposition of thin films of the corresponding binary materials by MOCVD processes could be demonstrated. In particular Lewis acid-base adducts R3M—ER3 and four- and six-membered heterocycles [R2MER x (Fig- 1) have been in the focus of research groups both in industry and university. Consequently, the development of powerful synthetic pathways for the preparation of such precursors has been forced. 

In order to assess how the bulk of the arene influences the structure of such stacked assemblies, the adducts of 137 with toluene, o-, m-, and -xylenes, and mesitylene have been synthesized and structurally characterized.236 These adducts tend to form extended binary stacks similar to those found in [137-benzene], The substituted benzene molecules adopt an apparently random orientation with respect to the trinuclear core of 137, thus suggesting that the binding might be... 

This review has described the synthesis, structure and reactivity of important classes of group 13/15 compounds such as Lewis acid base adducts and heterocycles. In addition, their potential to serve as single source precursors for the deposition of the corresponding binary materials by MOCVD process has been demonstrated. Because of the large number of compounds containing the lighter elements of group 15, N, P and As, these... 

Thioselenation of alkenes,209,210 1,3-dienes,207 and vinylcyclopropanes197 occurs by using the binary system of (PhS)2/(PhSe)2 to afford the adducts regioselectively in good yield (Table 6). Addition of a disulfide to fullerene[60] is achieved using this binary system.211... 

Perchloryl fluoride shows no tendency to form adducts with either strong Lewis acids or bases. This behavior has been rationalized in Section II, D. The binary systems of FCIO3 with BFa, PF5, AsFs, SbFj, or SO3 were studied by Lang 167), at Pennsalt 224), and by Nikitina and Rosolovskii 209). Similarly, at Pennsalt 224) no evidence was found for complexing of FCIO3 with either CsF or FNO2. 

The forth chapter by S. Schulz also deals with single-source precursors and provides a study case on CVD Deposition of Binary AlSb and GaSb Material Films - a Single-Source Approach . The article summarises recent studies on the synthesis of M-Sb compounds and their potential application as precursors in OMCVD processes. General reaction pathways for the synthesis of Lewis-acid-base adducts R3M-ER3 and heterocycles of the type [R2MSbR2 h (M = Al, Ga) are described. The results of deposition studies are discussed. 

---