Lithium hexamethyldisilazane LHMDS

The intramolecular aldol condensation route to fused tricyclic /3-lactams has been explored. The methylene group of an yV-tu-methoxycarbonyl alkyl chain is sufficiently acidic to react with a carbonyl group when treated with lithium hexamethyldisilazane (LHMDS) in THF at — 78 °C. Reaction times are short and yields high (Equation 59) <1996JOC7125>. 

GABA HMG-CoA HMPA HT LDA LHMDS LTMP NADH NBH NBS NCS NIS NK NMP PMB PPA RaNi Red-Al RNA SEM SnAt TBAF TBDMS TBS Tf TFA TFP THF TIPS TMEDA TMG TMP TMS Tol-BINAP TTF y-aminobutyric acid hydroxymethylglutaryl coenzyme A hexamethylphosphoric triamide hydroxytryptamine (serotonin) lithium diisopropylamide lithium hexamethyldisilazane lithium 2,2,6,6-tetramethylpiperidine reduced nicotinamide adenine dinucleotide l,3-dibromo-5,5-dimethylhydantoin A-bromosuccinimide A-chlorosuccinimide A-iodosuccinimide neurokinin 1 -methyl-2-pyrrolidinone para-methoxybenzyl polyphosphoric acid Raney Nickel sodium bis(2-methoxyethoxy)aluminum hydride ribonucleic acid 2-(trimethylsilyl)ethoxymethyl nucleophilic substitution on an aromatic ring tetrabutylammonium fluoride tert-butyldimcthyisilyl fert-butyldimethylsilyl trifluoromethanesulfonyl (triflyl) trifluoroacetic acid tri-o-furylphosphine tetrahydrofuran triisopropylsilyl A, N,N ,N -tetramethy lethylenediamine tetramethyl guanidine tetramethylpiperidine trimethylsilyl 2,2 -bis(di-p-tolylphosphino)-l,r-binaphthyl tetrathiafulvalene... 

LiHMDS lithium hexamethyldisilazane, lithium bis(trimethylsilyl)amide (LHMDS)... 

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