Untersuchungen über die Autoxidation von cis‐ und trans‐β‐Methylstyren

Abstract

Studies on the Autoxidation of cis‐ und trans‐β‐Methyl Styrene In the autoxidation of cis‐ and trans‐β‐methyl styrene at temperatures between 80 and 120°C the CC‐double bond is preferably attacked: 35–60% of epoxides and their consecutive products and 25–50% of benzaldehyde are obtained. Products of allylic oxidation are formed only with yields lower than 1%; high‐boiling or polymeric products, respectively, which could not be detected gaschromatographically are formed with yields lower than 20%. The ratio of cis‐ to trans‐epoxides in the case of cis‐β‐methyl styrene oxidation amounts to about 0.04, in the case of trans‐β‐methyl styrene oxidation this ratio is about 0.01.

Siloxymethylamines as Aminomethylation Reagents for Amines Leading to Labile Diaminomethanes That can be Trapped as Their [Mo(CO)4] Complexes

“…The 3D lattice structure is held together by hydrogen bonds of the type CH ⋅⋅⋅ OC ranging from 2.593(5) to 2.827(5) Å. This structure is similar to three triamine complexes described in the literature, that is, CoCl 2 [(Me 2 NCH 2 ) 2 NMe], and [Co(CO) 4 CuNMe 2 ) 2 NR (R=H and propyl), together with a similar biuret iridium complex, Ir(NH−CO−NH−CO−NH), both involving bidentate structural motif …”

Studies on the Autoxidation of Aryl Alkenes

“…From the evaluation of reported work on the oxidation of cyclo-octene [38], b-methyl-styrene [16,17], norbornene derivatives [39], and the present study, see Tab. 1 [20][21][22][23], it is evident that a selectivity greater then 50 % can be achieved for epoxide formation.…”

“…It is well known from the publications of F. R. Mayo [7], E. A. Blyumberg [33], and W. Pritzkow [10,16] that increasing reaction temperature favors epoxide formation. For example, in the oxidation of p-butyl-a-methylstyrene in chlorobenzene and in the presence of cumene and cumene hydroperoxide in the range of 65-125°C (see Fig.…”

“…A survey of the literature for the oxidation of styrene [7,10,12,13], substituted styrenes [12], a-and b-methyl styrene [14], and 1,1-diphenylethylene [15] reveals that the epoxide yield is strongly dependent on the structure of the olefin. Thus, at 90°C the selectivity for epoxide formation during the oxidation of styrene, a-methylstyrene, and cis-/trans-b-methylstyrene was approximately 10 %, 40 %, and 50 %, respectively [10,16,17].…”

Einige Gesetzmäßigkeiten bei der Autoxidation von Styrolderivaten

“…Die Literaturangaben zur Oxidation von Styrol [7, 8, 11 ± 17], kernsubstituierten Styrolen [14,15], 1,1-Diphenylethylen [20] und a-bzw. b-Methylstyrolen [18,19] zeigen, dass die Epoxidbildung stark von der Olefinstruktur abhängt. So liegt die Epoxid-Selektivität bei der Oxidation von Styrol bei 90 C bei 8 ± 10 %, für a-Methylstyrol bei 38 ± 41 % und für cis-bzw.…”