1,5‐Diketone

Abstract

Pan1 nud H o e r m a n n , Ber. d. dentsch. diem. Ges. 28, 32%. 50 -83.

The use of Hagemann's esters to prepare highly functionalized phenols and benzenes

“…One year after Hagemann's synthesis of 3, Knoevenagel improved its preparation by coupling 1 with formaldehyde to generate Michael acceptor 4 in situ, which reacts with a second molecule of 1 to yield diketone 2, 4 which in turn, undergoes intramolecular aldol reaction to produce cyclic alcohol 7. The mechanism of the formation of Hagemann's ester has been the subject of…”

“…For example, phenol 21 was converted into triflate 33 using pyridine and triflic anhydride (Scheme 7). Triflate 33 and the alkylborane formed by reacting 9-BBN with 1-octene were treated with Pd(PPh 3 ) 4 , to produce arene 34 in 57% yield. Triflate 35 was generated from phenol 32 in 86% yield.…”

Über die Einwirkung des Grignardreagenz auf die Amidgruppe XXIX. Reaktion des Grignardreagenz mit 1-Methyl-6-alkyl-3,4-dihydropyridonen-(2)

“…Kalilauge die Base freigesetzt und in Ather aufgenommen. Nach Trocknen mit Kaliumhydroxyd lieferte del' Atherauszug 9,6 g (41 %) 1, 2,3, In die Losung d es aus 142 g Methyljodid und 25 g Magnesium in 500 ml Ather bereiteten Grignardreagenz wurden nach AbdestiJIieren des Athers und Zufiigen von 300 ml Benzol 50 g 1,6-Dimethyl-3,4-dihydropyridon-(2) bei Siedetemperatur unter Riihren zugetropft und die Reaktion durch dreistiindiges Kochen am Wasserbad zu Ende gefiihrt. Die Zersetzung und Isolierung del' Produkte erfolgte in analoger W eise wie im vorhergehenden Versuch.…”

“…Die Neutralisation del' fliichtigen Basen erforderte 40,1 ml 6,59N-HCl (68%). Ausboute 4,3 g 1,2,2,2,3, Reaktion von 1-Methyl-6-iithyl-3,4-dihydropyridon-(2) (Ib) mit Athylmagnesiumbromid…”

Synthesis and structural conformation of N‐substituted 1,4‐dihyropyridine derivatives

“…The structure was determined by NMR and by hydrolysis of the keto alcohol product generated. As a result of the original [5] incorrect assignment subsequently has become the subject of a great deal of confusion in the literature [2,[6][7][8][9].…”