Diazomethyl‐phosphinoxyde

λ5-Phosphorus-Containing α-Diazo Compounds: A Valuable Tool for Accessing Phosphorus-Functionalized Molecules

“…On the contrary, the possibility of achieving phosphonopyrazolines by the reaction of PCDCs with activated alkenes has very few examples in the literature. In addition to the three papers from the 1960s, ,, discussed at the beginning of this section, Verma et al reported that the cycloaddition of BOR ( 22 ) to trisubstituted enones, such as 366a – f , could be “interrupted” at the pyrazolines stage (Table ). Under the established reaction conditions (KOH in MeOH; method A), the yields of the pyrazolines 367a – f were moderate with the reaction remaining incomplete in some case.…”

“…The ability of PCDCs to act, in the absence of a catalyst, as 1,3-dipoles in [3+2] cycloaddition reactions has been recognized since their discovery. Under purely thermal conditions, diphenyl α-diazomethylphosphinoxide ( 2a ) reacted with methyl vinyl ketone or dimethyl maleate to give the corresponding phospono-1-pyrazolines 329 and 330 (Figure ), both isolated in 70% yield, after crystallization of the crudes from methanol …”

“…Whereas no spectroscopic evidence supporting the structural assignment was provided by Kreutzkamp et al, so that the correctness of the structural assignment cannot be confirmed, IR and 1 H NMR spectroscopic data for compounds 331 – 334 were reported . In 1968, Regitz et al reported the synthesis of phosphono-2-pyrazolines by cycloaddition of diethyl diazobenzylphosphonate ( 20a ) and its 4-nitro analogue 20b with methyl vinyl ketone.…”

“…α-Diazomethylphosphinoxides 2b and 2c were synthesized a few years later by Kreutzkamp et al following the same methodology (Scheme 1). 29 In 1970, Seyferth 6,30 reported the preparation of the dimethyl α-diazomethylphosphonate (5a), which is the most popular among PCDCs. Compound 5a was synthesized by diazotization of dimethyl aminomethylphosphonate acetate salt (4a), which in turn was obtained by hydrazinolysis of dimethyl phthalimidomethylphosphonate (3a) (Scheme 2).…”

Synthesis of (Aminoalkyloxymethyl)dimethylphosphine Oxides

“…However, only few T P O 's containing one or more primary amino groups in their mole cules are known. Studies on such compounds are limited [6][7][8][9][10][11][12]. Because of the high activity of amino groups these compounds can be used as phosphorylation agents for polymers, as well in synthesis of new organophosphorus compounds.…”