86801-34-5

Upstream product

• 1885-14-9 phenyl chloroformate 
• 110-86-1 pyridine 
• 92273-73-9 n-butylzinc bromide 
• 86801-40-3 1-phenoxycarbonylpyridinium chloride 
• 94616-73-6 n-butylcerium dichloride 
• 59020-10-9 3-(tributylstannyl)pyridine 
• 693-04-9 butyl magnesium bromide 

Downstream Products

• 24152-39-4 4-n-butylpiperidine 
• 651053-81-5 phenyl 4-butylpiperidine-1-carboxylate 
• 5335-75-1 4-butylpyridine 
• 13509-27-8 methyl phenyl carbonate 

Relevant academic research and scientific papers

Efficient Solution-Phase Parallel Synthesis of 4-Substituted N-Protected Piperidines

Practical conditions for the synthesis of 4-substituted N-protected piperidines through CuCN·2LiBr-catalyzed organozinc additions to 1-acylpyridinium salts and subsequent hydrogen-transfer hydrogenation have been established. The reaction sequence is performed at room temperature and provides 4-substituted N-protected piperidines in excellent overall yields without the isolation of intermediate dihydropyridines, In those cases in which the organozinc addition results in mixtures of 2- and 4-substituted dihydropyridines, the 2-substituted isomers are efficiently scavenged with maleic anhydride and subsequently removed by a mild extractive workup with NaHCO3 (sat.). The N-acyl group can conveniently be exchanged from N-phenoxycarbonyl to N-tBoc, thus allowing orthogonal deprotection strategies. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.

Versatile Synthesis of Dihydroquinolines and Quinoline Quinones Using Cyclobutenediones. Construction of the Pyridoacridine Ring System

1-BOC-2-lithio-1, 4-dihydropyridines were condensed with 3,4-disubstituted cyclobutenediones to produce 1,2-adducts. Neat thermolysis under oxygen-free conditions produced substituted 1,4-dihydroquinoline hydroquinones in which the tert-butoxy residue of the BOC group was displaced by a phenolic residue, generating an oxazolone ring that functioned to protect both rings of the dihydroquinoline hydroquinone from untimely oxidation. Oxidative aromatization with concomitant loss of the oxazolone ring was achieved using 2 equiv of o-chloranil in acetic acid and provided substituted quinoline quinones in good yields. By use of this strategy, a concise synthesis of the pyridoacridine ring system was achieved.

A synthesis of quinoline-5,8-quinones via the benzannulation of 1,4-dihydro-2-pyridyl carbene complexes

A method for the preparation of quinoline-5,8-quinones is described with the key step the benzannulation of a dihydropyridyl Fischer carbene complex. The carbene complexes are generated by the standard Fischer method upon metallation of N-Boc protected 1,4-dihydropyridines and their reactions with alkynes to provide 1,4-dihydroquinolines. The latter are converted to quinoline,5,8-quinones by a two-step oxidation procedure involving eerie ammonium nitrate and trityl tetrafluoroborate.

REGIOSELECTIVE ADDITION OF NUCLEOPHILES TO 1-(PHENOXYCARBONYL)-3-TRIALKYLSTANNYLPYRIDINIUM SALTS

The regioselectivity of nucleophilic addition to 1-(phenoxycarbonyl)-3-trialkylstannylpyridinium salts was studied.

α-METALATION OF 1-(TERT-BUTOXYCARBONYL)-1,4-DIHYDROPYRIDINES

The α-metalation-alkylation of 4-substituted 1-(tert-butoxycarbonyl)-1,4-dihydropyridines is described.Subsequent aromatization provides a new route to 2,4-disubstituted pyridines.