71653-11-7Relevant academic research and scientific papers
Expansion of substrate scope for nitroxyl radical/copper-catalyzed aerobic oxidation of primary alcohols: A guideline for catalyst selection
Iwabuchi, Yoshiharu,Nagasawa, Shota,Sasaki, Ryota,Sasano, Yusuke,Yamaichi, Aoto
, p. 488 - 497 (2021/05/27)
Four distinctive sets of optimum nitroxyl radical/copper salt/additive catalyst combinations have been identified for accommodating the aerobic oxidation of various types of primary alcohols to their corresponding aldehydes. Interestingly, less nucleophilic catalysts exhibited higher catalytic activities for the oxidation of particular primary allylic and propargylic alcohols to give α,β-unsaturated aldehydes that function as competent Michael acceptors. The optimum conditions identified herein were successful in the oxidation of various types of primary alcohols, including unprotected amino alcohols and divalent-sulfur-containing alcohols in good-to-high yields. Moreover, N-protected alaninol, an inefficient substrate in the nitroxyl radical/ copper-catalyzed aerobic oxidation, was oxidized in good yield. On the basis of the optimization results, a guideline for catalyst selection has been established.
Stereocontrolled synthesis of a Cn-Cn+7 building block ("eastern moiety") for the unnatural enantiomers of important polyol,polyene antibiotics based on a ring-closing metathesis and an aldol addition of a lactone enolate
Kamptmann, Sonja B.,Brueckner, Reinhard
supporting information, p. 6584 - 6600 (2013/11/06)
A stereocontrolled synthesis of epoxide 6, which represents the C n-Cn+7 or "eastern moiety" building block for the title compounds, has been realized in 19 steps. Our synthesis started from tetrabromoacetone 26 and afforded dibromotriene 33b in six steps. The latter was subjected to a ring-closing metathesis, which gave the dibromovinyl-substituted lactone 34 in high yield. A highly stereoselective conjugate addition/enolate aldolization sequence established the additional stereocenters with perfect selectivity. Epoxide 47b was reached in another eight steps, which included a C-SiMe2Pha€‰→a€‰C-OH oxidation in the presence of an acetal group. The final structure 6 was completed by hydrostannylation/brominolysis. A dibromovinyl-substituted unsaturated δ-lactone obtained by ring-closing metathesis underwent a highly diastereoselective silyl cuprate 1,4-addition/aldolization sequence. Tamao-Fleming oxidation transformed the silyl into a hydroxy group. Alkyne formation, hydrostannylation, and N-bromosuccinimidolysis converted the dibromovinyl into a trans-bromovinyl moiety. Copyright
Total synthesis of (-)-maysine
Meyers,Babiak,Campbell,et al.
, p. 5015 - 5024 (2007/10/02)
A convergent synthesis of the natural macrocycle (-)-maysine (3) has been accomplished involving only a single separation of epimers at C-10. The scheme involved the preparation of three major fragments: (a) the western zone, 4; (b) the southern zone, 6;
