Phosphoniosilylation

P-Alkylation of enonesS The products (1) of phosphoniosilylation of enones (14,60) react with activated alkenes in the presence of TMSOTf in THF at - 78° to give p-alkylated products. 

A new approach to the 0-functionalisation of enones involves treating the substrate with t-butyldimethylsilyl triflate (TBDMSOTf) in the presence of triphenylphosphine. This phosphoniosilylation reaction gives a silylenol ether-wittig salt which, after lid formation, may be condensed with an aldehyde to give a silyl dienol ether. These may either be protiodesilylated to give the 0-functionalised enone or alternatively used in aldol... 

Phosphoniosilylation. Cyclic enones treated with TBDMS triflate and triphenylphosphine in THF at it provide the corresponding l-(3-f-butyldimethylsilyloxy-2-cycloalkenyl)triphenyl-phosphonium triflates (eq 8) which, upon lithiation with n-butyllithium followed by Wittig reaction with aldehydes, afford various conjuated dienes. ... 

---

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ , , ]

---