201008-68-6

Upstream product

• 768-66-1 2,2,6,6-tetramethyl-piperidine 
• 100-07-2 4-methoxy-benzoyl chloride 
• 123-11-5 4-methoxy-benzaldehyde 
• 38227-87-1 2,2,6,6-tetramethylpiperidinyl-lithium 

Relevant academic research and scientific papers

Carbolithiation of aromatic rings: Cyclohexadienes from N-aroyl-2,2,6,6-tetramethylpiperidines

Benzamides whose nitrogen atom is part of a 2,2,6,6-tetramethylpiperidine ring are dearomatised by alkyllithiums, which attack them regioselectively to yield, after electrophilic quench, substituted cyclohexadienes.

Gram-Scale Preparation of Acyl Fluorides and Their Reactions with Hindered Nucleophiles

A series of acyl fluorides was synthesized at 100 mmol scale using phase-transfer-catalyzed halogen exchange between acyl chlorides and aqueous bifluoride solution. The convenient procedure consists of vigorous stirring of the biphasic mixture at room temperature, followed by extraction and distillation. Isolated acyl fluorides (usually 7-20 g) display excellent purity and can be transformed into sterically hindered amides and esters when treated with lithium amide bases and alkoxides under mild conditions.

Intermolecular dearomatising addition of organolithium compounds to N-benzoylamides of 2,2,6,6-tetramethylpiperidine

N-Benzoylamides of 2,2,6,6-tetramethylpiperidine are not ortholithiated by organolithium compounds but instead undergo nucleophilic addition of the organolithium compound to the aromatic ring in the manner of a conjugate addition. The resulting dearomatised enolates may be protonated or alkylated, and yield substituted cyclohexadienes in yields of up to 76%. Deprotection of the piperidine ring is possible under acidic conditions. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.

Isochroman-3-ones ones via site-selective ring opening of benzocyclobutenones promoted by lithium tetramethylpiperidide and reaction with aromatic aldehydes

In the presence of Li-TMP and an aromatic aldehyde, benzocyclobutenone undergoes an unusual heterolytic C(1)-C(4) bond fission, and subsequent reaction with the aldehyde gives, after acidic workup, isochroman-3-one in high yield.