ChemInform Abstract: ALKYLOXY AND SILYLOXY DERIVATIVES OF PHOSPHORUS(V) AND ANTIMONY(V)

Abstract

Nach einleitenden Untersuchungen zur Thermolyse der Alkoxy‐Verbindungen (I) wird deren Reaktion und die von (II) mit Triphenylsilanol (III) zu (IV) bzw. (VII) beschrieben.

Arylation reactions with organobismuth reagents

“…An organoantimony betaine product was postulated to be formed when pentaphenylbismuth was reacted with triphenylantimony in carbon tetrachloride solution. 96 The betaine was neither isolated nor detected, the reaction mixture being treated with hydrogen chloride.…”

“…In moist pyridine, the products included phenol and diphenyl ether, diphenyl ether being formed by reaction of pentaphenylbismuth with phenol. 95 In the presence of tert-butyl alcohol, tert-butyl phenyl ether was obtained. Diels-Alder addition products were obtained with furan and with 2,3,4,5-tetraphenylcyclopentadienone.…”

“…Diels-Alder addition products were obtained with furan and with 2,3,4,5-tetraphenylcyclopentadienone. 78,96 PhgBi + H20 -PhOH…”

“…The first example was the formation of diphenyl ether during the decomposition of pentaphenylbismuth in the presence of phenol.96, 96 The major impetus came from the reaction of pentaphenylbismuth with 4nitrophenol, leading exclusively to 4-nitrodiphenyl ether. 79 The selective O-phenylation of a phenol substituted with an electron-withdrawing group by pentaphenylbismuth developed into a study of the reaction of electron-rich phenols with pentavalent organobismuth reagents bearing electron-withdrawing groups under neutral conditions.108 A variety of phenols were O-phenylated through reaction with tetraphenylbismuthonium acylate (Ph4BiOCOR with R = CH3 or CF3) or tetraphenylbismuthonium p-toluenesulfonate under neutral conditions.…”

Pentavalent organobismuth reagents. Part 2. The phenylation of phenols

“…Mechanistic Considerations.-We have previously suggested that reaction of 2-naphthol(l) with pentavalent organobismuth reagents (Ph,BiX or Ph,Bi) under neutral conditions involves the formation of an intermediate (4)3 possessing a covalent bismuth-xygen bond, and that the breakdown of this intermediate to give l-phenyl-2-naphthol (2) or 2-naphthyl phenyl ether (3) is determined by the nature of the ancillary group X (X = electron-withdrawing group or phenyl) in the intermediate (4). Our reason for postulating the existence of the intermediate (4) was provided by the observation that in addition to the product (3), benzene was also formed when 2-naphthol (1) was treated with tetraphenylbismuth trifluoro- acetate under neutral condition^.^ We postulated that the breakdown of the intermediate (4) occurred to give either 2-naphthyl phenyl ether (3) when the group X was strongly electron-withdrawing, or l-phenyl-2-naphthol (2) when the group X was phenyl. In accord with this postulate, 2-naphthol (1) and tetraphenylbismuth trifluoroacetate afforded, under neutral conditions with elimination of benzene only, the Ophenylated product (3),3 whereas 2-naphthol (1) and pentaphenylbismuth afforded only the C-phenylated product (2).…”