β-functionalization of enones via phosphoniosilylation = 포스포니오실릴레이션을 통한 α,β-불포화 케톤의 작용기화 ;

Cited 0 time in webofscience Cited 0 time in scopus
  • Hit : 343
  • Download : 0
I. β-Functionalization of Enones via Phosphoniosilylation β-Alkoxycarbonylation, β-acylation, and β-sulfenylation of α,β-enones are achieved by the reaction of ylides, derived from enones via phosphoniosilylation, with benzyl chloroformate, benzoyl fluoride, and diphenyl disulfide, respectively, followed by the desilylation. β-Conjugate addition and β-hydroxyalkylation of α,β-enones have been accomplished by the reaction of ylides with activated olefins and aldehydes in the presence of trimethylsilyl triflate in tetrahydrofuran at -78℃ and subsequent elimination of phosphonium salts by one-pot procedure. Also, direct displacement of triphenylphosphonium salt, derived from enones via phosphoniosilylation, with several nucleophiles provides conjugate addition products in which ketone groups are protected as silylenol ethers. II. Synthesis of β-Lactams from β-Amino Acids Using Organophosphorus Reagents. Diphenylphosphinic chloride is found to be very effective condensing reagent for the formation of β-lactams from N-substituted β-amino acids. Bis(5-nitro-2-pyridyl) phenyl phosphate (NPPP) and bis(5-nitro-2-pyridyl) phenylphosphonate (BNPP) are prepared by the reaction of phenyl dichlorophosphate and phenylphosphonic dichloride, respectively, with 2-hydroxy-5-nitropyridine. NPPP and BNPP can be effectively utilized as a condensing reagent for the formation of β-lactams from N-substituted β-amino acids. Using triphenylphosphine/carbon tetrachloride system as a condensing reagent, N-substituted as well as N-unsubstituted β-amino acids are cleanly cyclized into the corresponding β-lactams in high yields under a concentrated solution.
Advisors
Kim, Sung-Gakresearcher김성각researcher
Description
한국과학기술원 : 화학과,
Publisher
한국과학기술원
Issue Date
1989
Identifier
61267/325007 / 000845264
Language
eng
Description

학위논문(박사) - 한국과학기술원 : 화학과, 1989.2, [ ix, 166 p. ]

URI
http://hdl.handle.net/10203/31323
Link
http://library.kaist.ac.kr/search/detail/view.do?bibCtrlNo=61267&flag=dissertation
Appears in Collection
CH-Theses_Ph.D.(박사논문)
Files in This Item
There are no files associated with this item.

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0