Polystyryl-mercury trifluoroacetate. A convenient and mild reagent for thioacetal and thioketal hydrolysis

1982 ◽  
Vol 47 (11) ◽  
pp. 2212-2213 ◽  
Author(s):  
Vaclav Janout ◽  
Steven L. Regen
Keyword(s):  
Mercury Trifluoroacetate

Synthèse du (±)-loliolide ou hydroxy-6 tétrahydro-5,6,7,7a triméthyl-4,4,7a(4H) benzofurannone-2 (6S,7aR) par cyclisation de l'acide homogéranique

1984 ◽  
Vol 62 (11) ◽  
pp. 2326-2329 ◽  
Author(s):  
Henri Zamarlik ◽  
Noukpo Gnonlonfoun ◽  
Francis Rouessac
Keyword(s):  
New Synthesis ◽  
Mercury Trifluoroacetate

Starting from pure homogeranic acid 2, in a stereoselective fashion, we describe a new synthesis of (±)-loliolide 1. Cyclization of 2 with mercury trifluoroacetate or phenylselenenyl chloride provides the isodihydroactinidiolide 6 which was converted to the racemate of loliolide after six steps.[Formula: see text]

scholarly journals Preparation of diversely protected 2-azido-2-deoxyglycopyranoses from glycals

1995 ◽  
Vol 73 (3) ◽  
pp. 343-350 ◽  
Author(s):  
Stanislas Czernecki ◽  
Ebtissam Ayadi
Keyword(s):  
Sodium Azide ◽  
Protecting Groups ◽  
Hydroxyl Group ◽  
High Yield ◽  
Second Step ◽  
Trimethylsilyl Azide ◽  
Free Hydroxyl ◽  
Second Procedure ◽  
Hydrolysis Of ◽  
Mercury Trifluoroacetate

A new and efficient preparation of diversely protected 2-azido-2-deoxyglycopyranosides from the corresponding glycals is described. The glycals are first transformed into protected phenyl 2-azido-2-deoxy-selenoglycopyranosides by azido-phenylselenylation. Two procedures were employed according to the protecting groups present: sodium azide and diphenyldiselenide in the presence of (diacetoxyiodo)benzene for peracetylated glycals (Procedure A) or trimethylsilyl azide and tetra-n-butylammonium fluoride in the presence of N-phenylselenophthalimide for perbenzylated glycals (Procedure B). A gluco–manno mixture (90%) is obtained from protected d-glucal whereas only the galacto isomer is formed from protected d-galactal (75%). The compatibility of the second procedure with one free hydroxyl group and a variety of protecting groups was verified with 1,5-anhydro-2-deoxy-3,4-O-isopropylidene-d-lyxo-hex-1-enitol and its 6-O-acetyl, 6-O-allyl, 6-O-benzyl, and 6-O-tert-butyldimethylsilyl derivatives as well as with 1,5-anhydro-4,6-O-benzylidene-2-deoxy-d-lyxo-hex-1-enitol and its 3-O-acetyl and 3-O-benzyl derivatives, which were transformed into phenyl 2-azido-2-deoxy-α-d-selenogalactopyranoside derivatives in good yield. In the second step, hydrolysis of these selenoglycosides afforded diversely protected glycopyranoses in high yield. Peracetylated derivatives were hydrolyzed in the presence of N-iodosuccinimide, whereas mercury trifluoroacetate was employed for 3,4-O-isopropylidene, 4,6-O-benzylidene, and perbenzylated derivatives. In some cases the two steps can be carried out without isolation of the intermediate selenoglycoside. Keywords: glycals, 2-azido-2-deoxygalactopyranose, 2-azido-2-deoxyglucopyranose, selenoglycosides.

Promoting effect of mercury trifluoroacetate on transnitrilation reactions

1989 ◽  
Vol 40 (2) ◽  
pp. 327-329 ◽  
Author(s):  
V. A. Vinokurov ◽  
E. G. Gaevoi ◽  
T. K. Mamedova ◽  
Z. M. Movsumzade ◽  
R. A. Karakhanov
Keyword(s):  
Promoting Effect ◽  
Mercury Trifluoroacetate
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