Ring expansion in the addition of dichlorocarbene to 2,5-dihydro-1H-phosphole 1-oxides

A new family of platinum(II) complexes incorporating five‐ and six‐membered cyclic phosphine ligands

“…The chosen P-heterocycles, 3-methyl-and 3,4-dimethyl-1-phenyl-3-phospholene oxides (1a [26] and 1b [27], respectively), 3-methyl-and 3,4-dimethyl-1-phenylphospholane oxides (5a [28] and 5b [29], respectively), 4-dichloromethylene-3,5-dimethyl-1-phenyl-1,4-dihydrophosphinine oxide 9 [30], and 5-methyl-1-phenyl-4-chloro-1,2,3,6-tetrahydrophosphinine oxide 12 [31] were subjected to a standard deoxygenation procedure by trichlorosilane in the presence of pyridine in boiling toluene [32]. With one exception (10), the phosphines so obtained, 2a, 2b, 6a, 6b, and 13 were reacted with dimethylsulfide borane and identified as the corresponding phosphine-boranes 3a, 3b, 7a, 7b, and 14, respectively.…”

“…Phospholene oxides 1a and 1b were prepared as described earlier [26,27]. Phospholane oxides 5a and 5b were synthesized by the catalytic hydrogenation of compounds 1a and 1b [28,29].…”

<strong>The potential and scope of the microwave tool; A case study on the synthesis of phosphinates&nbsp;</strong>

“…This classical protocol is exemplified by the esterification of 1-chloro-3-phospholene 1-oxides (Scheme 1/A) [13,14]. The use of phosphinic chlorides means cost, and causes environmental burden due to the HCl formed.…”

Alkylating esterification of 1‐hydroxy‐3‐phospholene oxides under solventless MW conditions

“…The phosphinic chlorides may be prepared from the corresponding phosphinic acids by reaction with inorganic chlorides. The method is also applicable for the synthesis of cyclic phosphinates, such as 1-alkoxyphospholene 1-oxides (3) involving the hydroxyphospholene oxide (2) as the starting material and the chlorophospholene oxide (4) as the intermediate (Scheme 1) [3,4]. The alkoxyphospholene oxides (3) can also be obtained directly by the alcoholysis of the phospholium salts (1) [5][6][7] available from the McCormack cycloaddition of a variety of dienes with phosphorus tribromide.…”