The use of SO2Cl2 in organometallic chemistry. Convenient high yield syntheses of [Fe(η-C5H5)(CO)3] [FeCl4] and [M(CO5Cl] (M = Mn or Re)

Depending on the substrate and the reaction conditions, SO₂Cl₂ is a useful reagent which brings about either chlorination or the formation of cationic species on reaction with transition metal carbonyl complexes.     

Characteristic free, improved decidability criteria for the similarity problem

In [1], the authors derived algebraic criteria, expressible as a first order sentence in field theory, for the similarity of two matrices over a field of characteristic zero. It thus follows from a well-known result in model theory that this criteria is valid for sufficiently large characteristics, while all of our philosophy and techniques, save one, remain valid in arbitrary characteristics. The characteristic zero phenomenon is contained in the Clebsch-Gordan Theorem or rather in one of its consequences, Roth's Lemma. In order to avoid the use of Roth's Lemma, we have devised an alternate proof which also gives much more simplified criteria, valid in arbitrary characteristic and denned over nonalgebraically closed fields.     

Chemistry of singlet Oxygen. XXVII. Directing effect of methoxy group in additions to methoxystyrenes

A methoxy group on a styrene double bond directs O₂ attack $\text{cis}$, giving 1,4 addition if the phenyl is $\text{cis}$, or ene reaction if a CH₃ is $\text{cis}$. If no substituent is $\text{cis}$, 1,4 attack on the $\text{trans}$ phenyl occurs at a slower rate.     

Triangulations and frieze patterns

Journal of Geometry -