Synthese von 3,5‐disubstituierten und 3,4,5‐trisubstituierten λ³‐Phosphorinen aus 1‐tert‐Butyl‐1,6‐dihydro‐3(2H)‐phosphorinonen

Abstract

5-Aryl-l-tert-butyl-l,6-dihydro-3(2H)-phosphorinone 13 -durch Reduktion der Phosphanoxide 1 mit Phenylsilan glatt zuganglich -reagieren mit 1 mol RMgX (RLi) ausschlieBlich unter Bildung der Enolate, mit 6 mol RMgX (RLi) hingegen werden nach mehrtagigen Reaktionszeiten direkt die 3-Aryl-l-ferl-butyl-l,2-dihydro-5-R-phosphorine 10 erhalten, die bei der Thermolyse zu den 3-Aryl-5-R-h3-phosphorinen 11 (R = Aryl, Alkyl, Heteroaryl) zerfallen. -5-Aryl-1-fertbutyl-l,6-dihydro-4-methyl-3(2H)-phosphorinone 19 reagieren rnit 5 -6 mol RMgX (RLi) entsprechend zu den 3-Aryl-l-rert-butyl-1,2-dihydro-4-methyl-5-R-phosphorinen 20, deren Thermolyse die 3-Aryl-4-methyl-5-R-h3-phosphorine 21 liefert. -Die 'H-, I3C-, "P-NMR-und UVSpektren der dargestellten h3-Phosphorine werden diskutiert. -Das aus 3,5-Diphenyl-h3-phosphorin ( l l e ) zugangliche 1 ,I-Dimethoxy-3,5-diphenyl-h5-phosphorin (22a) kuppelt mit Diazoniumsalzen zu den 2,4,6-Tris(aryIazo)-l ,I-dimethoxy-3.5-diphenyl-h5-phosphorinen 23.Synthesis of 3,5-DisubsIiIuted and 3,4,5-Trisubstituted A3-Phosphorins from l-rerf-Butyl-l,6-dihydro-3(2H)-phosphorinones 5-Aryl-l-lerf-butyl-l,6-dihydro-3(2H)-phosphorinones 13 -easily available by reduction of the phosphane oxides 1 with phenylsilane -react with 1 rnol of RMgX (RLi) exclusively by formation of the enolates, however with 6 mol of RMgX (RLi), after reaction times of several days, immediately the 3-aryl-l-lert-butyl-l,2-dihydro-5-R-phosphorins 10 are formed, which can be thermolyzed to give the 3-aryl-5-R-h3-phosphorins 11 (R = aryl, alkyl, heteroaryl). -5-Aryl-lferl-butyl-l,6-dihydro-4-methyl-3(2H)-phosphorinones 19 react with 5 -6 rnol of RMgX (RLi) similarly by formation of the 3-aryl-l-fer~-butyl-l,2-dihydro-4-methyl-5-R-phosphorins 20, whose thermolysis yields the 3-aryl-4-methyl-5-R-h3-phosphorins 21. The 'H, I3C, "P NMR and UV spectra of the synthesized h3-phosphorins are discussed. -1 ,l-Dimethoxy-3,5-diphenylh5-phosphorin (22a), availabls from 3,5-diphenyl-h3-phosphorin (11 e), undergoes coupling reaction with diazonium salts to give the 2,4,6-tris(aryIazo)-l ,I-dimethoxy-3,5-diphenyl-h5-phosphorins 23. 3,5-Disubstituierte L3-Phosphorine 11Wir berichteten kurzlich uber die Synthese der 3-Aryl-h3-phosphorine 3 durch Thermolyse der 3-Aryl-l-terf-butyl-l-chlor-h5-phosphorine 2, die ihrerseits bei der Umsetzung der 5-Aryl-1-terfbutyl-l,6-dihydro-3(2H)-phosphorinon-l-oxide 1 rnit Silicochloroform erhalten werden I.*).Auf dem gleichen Wege gelang uns die Darstellung der 3-Aryl-4-methyl-h3-phosphorine 6 aus den 5-Aryl-l-terl-butyl-l,6-dihydro-4-methyl-3(2H)-phosphorinon-l-oxiden 4 uber die entsprechenden h5-Phosphorine S3). 12Die Methylengruppen in dern P-Ketophosphanoxid-bzw. dern hierzu vinylogen Strukturelernent in l a , Ar = C6H5, erwiesen sich nun allerdings als so acid, daR eine Addition der metallorganischen Nucleophile an der Ketocarbonylgruppe zurn Carbinol nicht rnoglich ist, statt dessen bildete sich in allen untersuchten Fallen das Enolat 12a (oder 12a'), das nach der hydrolysierenden Aufarbeitung zurn Edukt 1 a...

Protodesilylation of 2,6-Disubstituted Silyphosphinines. Experimental and Theoretical Study

“…Though many synthetic approaches toward functional phosphinines have been devised, most of these studies focused on the elaboration of 2,6-disubstituted derivatives and methods providing a convenient access toward 3,5-disubstituted compounds have been much less studied. In most cases, these approaches rely on multistep procedures that are specific from the nature of the functional groups grafted at the 3 and 5 positions. − A few years ago we reported a synthetic strategy, which allows the synthesis of tetrafunctional derivatives. Polyfunctional compounds, − polydentate ligands, , and phosphorus macrocycles − could be easily prepared from disubstituted alkynes and 1,3,2-diazaphosphinine 1 through a cycloaddition/cycloreversion sequence which is depicted in Scheme .…”