27350-45-4Relevant academic research and scientific papers
An efficient method for the preparation of N-alkylamides from alkyl diphenylphosphinites and amides by using methyl acrylate
Aoki, Hidenori,Mukaiyama, Teruaki
, p. 456 - 457 (2007/10/03)
N,N-Dibenzyltrifluoroacetamide was formed in good yield by treating benzyl diphenylphosphinite with N-benzyltrifluoroacetamide in the presence of easily available methyl acrylate under mild conditions. Yields obtained for the corresponding inverted sulfon
Mechanism of decomposition of quasiphosphonium intermediates: Borderline SN1 character of alkyl-oxygen fission in sec-alkyloxyphosphonium salts
Hudson,Qureshi
, p. 473 - 480 (2007/10/03)
Short-lived alkoxyphosphonium intermediates have been detected in the interactions of alkyl diphenylphosphinites ROPPh2 (R = Et, Pr i, Bu8, and 3-pentyl) with iodomethane at room temperature. Phosphorus chemical shifts for the sec-alkoxy(methyl) diphenylphosphonium iodides (δp 68.6-68.7 ppm) are at slightly higher field than for ethoxy(methyl)diphenylphosphonium iodide (δp 72.4 ppm), in accord with higher electron density at phosphorus in the secondary alkyl sytems. Relative rates of decomposition in CDCl3 (Me > Et > Pri ? neopentyl) are in accord with SN2-type cleavage of the R-O bond but within the secondary alkyl series the relative rates (Pri 8 N1 mechanism is proposed.
Efficient method for the preparation of carboxylic acid alkyl esters or alkyl phenyl ethers by a new-type of oxidation-reduction condensation using 2,6-dimethyl-1,4-benzoquinone and alkoxydiphenylphosphines
Shintou, Taichi,Kikuchi, Wataru,Mukaiyama, Teruaki
, p. 1645 - 1667 (2007/10/03)
A new-type of oxidation-reduction condensation proceeded smoothly to afford carboxylic acid alkyl esters or alkyl phenyl ethers in good to high yields by combined use of alkoxydiphenylphosphines (1) having primary, bulky secondary or tertiary alkoxy groups, a mild quinone-type oxidant such as 2,6-dimethyl-1,4-benzoquinone (DMBQ) and carboxylic acids or phenols. Generally, alkoxydiphenylphosphines were prepared easily from chlorodiphenylphosphine (2) and alcohols in the presence of pyridine, and were isolated by distillation. On the other hand, the phosphines 1 were also prepared in situ from N,N-dimethylaminodiphenylphosphine (3a) and primary or secondary alcohols while primary, bulky secondary or tertiary alkoxydiphenylphosphines were alternatively formed in situ by adding 2 to the "BuLi-treated alcohols in order to perform the above reactions by a one-pot procedure from alcohols and nucleophiles. The reaction of thus formed 1, DMBQ and carboxylic acids or phenols afforded the corresponding alkylated products, including hindered secondary and tertiary alkylated ones, in good to high yields at room temperature. In the case of using chiral secondary alcohols, the corresponding carboxylic acid alkyl esters were obtained as well in high yields with perfect inversion of stereochemistry by SN2 replacement.
Preparation of various carboxylic acid esters from bulky alcohols and carboxylic acids by a new type oxidation-reduction condensation using 2,6-dimethyl-1,4-benzoquinone
Mukaiyama, Teruaki,Kikuchi, Wataru,Shintou, Taichi
, p. 300 - 301 (2007/10/03)
A new-type oxidation-reduction condensation by using 2,6-dimethyl-1,4-benzoquinone (DMBQ), carboxylic acids and in situ formed alkoxydiphenylphosphines (1) including the bulky alkoxy group-substituted ones proceeded smoothly to afford the corresponding carboxylic acid esters in good to high yields. Alkoxydiphenylphosphines were formed in situ by treating either N,N-dimethylaminodiphenylphosphine (Ph2PNMe2) with primary or secondary alcohols or chlorodiphenylphosphine with the lithium salts of primary, secondary and tertiary alcohols.
