6 research outputs found
Dehydration of amides to nitriles under conditions of a catalytic appel reaction
A highly expedient protocol for a catalytic Appel-type dehydration of amides to nitriles has been developed that employs oxalyl chloride and triethylamine along with triphenylphosphine oxide as a catalyst. The reactions are usually complete in less than 10 min with only a 1 mol % catalyst loading. The reaction scope includes aromatic, heteroaromatic, and aliphatic amides, including derivatives of Ī±-hydroxy and Ī±-amino acids
Catalytic asymmetric crotylation of aldehydes: application in total synthesis of (ā)āelisabethadione
A new, highly efficient Lewis base catalyst for
a practical enantio- and diastereoselective crotylation of
unsaturated aldehydes with E- and Z-crotyltrichlorosilanes
has been developed. The method was employed as a key
step in a novel asymmetric synthesis of bioactive serrulatane diterpene (Ć)-elisabethadione. Other strategic reactions for setting up the stereogenic centers included
anionic oxy-Cope rearrangement and cationic cyclization.
The synthetic route relies on simple, high yielding reactions and avoids use of protecting groups or chiral auxiliaries
Asymmetric total synthesis of (-)-erogorgiaene and its C11 epimer and investigation of their antimycobacterial activity
A short, nine-step, highly enantioselective synthesis of (ā)-erogorgiaene and its C-11 epimer is reported. The key stereochemistry controlling steps involve catalytic asymmetric crotylation, anionic oxy-Cope rearrangement and cationic cyclisation. (ā)-Erogorgiaene exhibited promising antitubercular activity against multidrug-resistant strains of Mycobacterium tuberculosis
Oxidative Dehomologation of Aldehydes with Oxygen as a Terminal Oxidant
A mild, efficient
protocol for oxidative cleavage of CāC
bonds in aldehydes has been developed that employs alkali metal hydrides
as reagents and oxygen from air as a terminal oxidant. The method
is applicable to a broad substrate range
Oxidative AzoāEne Cyclization
An expedient procedure for catalytic
oxidative azoāene cyclization
of allylic and homoallylic 1,2-hydrazinedicarboxylates is reported.
The reaction produced a wide range of cyclic carbamate derivatives
featuring an appended alkene fragment ready for further functionalization
Dehydration of Amides to Nitriles under Conditions of a Catalytic Appel Reaction
A highly expedient
protocol for a catalytic Appel-type dehydration
of amides to nitriles has been developed that employs oxalyl chloride
and triethylamine along with triphenylphosphine oxide as a catalyst.
The reactions are usually complete in less than 10 min with only a
1 mol % catalyst loading. The reaction scope includes aromatic, heteroaromatic,
and aliphatic amides, including derivatives of Ī±-hydroxy and
Ī±-amino acids