P-O Bond Formation
Phosphorylation of amines, alcohols, and sulfoximines provides various phosphoramidates, phosphorus triesters and sulfoximine-derived phosphoramidates using molecular iodine as a catalyst and H2O2 as the sole oxidant under mild reaction conditions.
J. Dhineshkumar, K. R. Prabhu, Org. Lett., 2013, 15, 6062-6065.
A metal-, toxic chloride reagent-free activating strategy of various phosphates with Tf2O and pyridine enables a facile synthesis of functional phosphates such as alkyl phosphates, aza phosphates, thiophosphate, and mixed diaryl phosphates via a transient phosphorylpyridin-1-ium species.
H. Huang, J. Ash, J. Y. Kang, Org. Lett., 2018, 20, 4983-4941.
Reaction of phosphorus oxychloride with a primary alcohol and triethylamine in toluene, followed by filtration and treatment with steam, gives dialkyl phosphates in good yield and essentially free from trialkyl phosphate impurities.
R. A. Aitken, C. J. Colett, S. T. E. Mesher, Synthesis, 2012, 44, 2515-2518.
An efficient electrophilic fluorination of secondary phosphine oxides with Selectfluor provides direct access to phosphoric fluorides in good yield under mild conditions. In addition, one-pot P-O bond construction is achieved in the presence of water or alcohols to provide phosphinic acids or phosphinates.
Q. Chen, J. Zeng, X. Yan, Y. Huang, C. Wen, X. Liu, K. Zhang, J. Org. Chem., 2016, 81, 10043-10048.
An electrochemical cross-dehydrogenative-coupling reaction between alcohols and secondary phosphine oxides provides organophosphinates in an eco-friendly and efficient manner at room temperature without the addition of any oxidant, metal catalyst, or additive.
L. Deng, Y. Wang, H. Mei, Y. Pan, J. Han, J. Org. Chem., 2019, 84, 949-956.
Copper catalysis allows the direct oxygen-arylation of dialkyl phosphonates with diaryliodonium salts. This reaction proceeds with a wide range of phosphonates and phosphoramidates under mild conditions and gives mixed alkyl aryl phosphonates in very good yields and very good selectivity.
M. Fañanás-Mastral, B. L. Feringa, J. Am. Chem. Soc., 2014, 136, 9894-9897.