Metallo aldimines. Masked acyl carbanion

Abstract

8) 2,4,6-Trimethylpyrimldine has been shown to undergo metalatlon with phenyllithium exclusively at the 4-methyl group.6 (9) (a) 2-Methyl-4(3H)-quinazolinone has been shown to undergo condensation at the methyl group with chloral: P. Y. Kulkarnl, J. Indian Chem. Soc.. 19, 180 (1942). (b) The N-phenyl derivative also has been reported to undergo similar reactions with other aldehydes: B. D. Singh and D. N. Chaudbury, ibid.. 45, 311 (1968). (c) Alkylation of 2-methyl-4(3H)-quinazolinone employing sodium hydride reportedly gives only Nand O-alkylated products:

Isocyanide in der Synthese von Stickstoff‐Heterocyclen

“…Organolithium‐93 ebenso wie Organomagnesiumreagentien94 können eine α‐Addition an Isocyanide eingehen und dabei metallierte Aldimine ergeben, die die Möglichkeit einer Cyclisierung zu N‐Heterocyclen bieten, sofern eine geeignete benachbarte funktionelle Gruppe im gleichen Molekül erzeugt wird oder vorhanden ist. So wurde z.…”

2′‐Nitro‐2′‐propen‐1′‐yl 2,2‐Dimethylpropanoate (NPP), A Multiple Coupling Reagent

“…4243". IR (CCl,): 3000, 2945, 2920, 2850, 1655, 1610, 1520, 1480, 1440, 1420, 1340, 1242, 1150, 1028 (4), 158 (32), 144 (25), 143 (IOO), 129 (25), 128 (25), 115 (14), 105 (6), 91 (12), 77 (7), 65 (5). Anal.…”

“…IR (CCI,): 3080,3060,3020,2940,2890,2842,2817,1595,1572,1520,1500,1440,1420,1365,1336,1246,1209,1190,1158,1119,1030,1000,984,948,901,860,690,670,630. 'H-NMR (CCI,): 2.99 (s, 3H, CH3N); 4.4 (m, 2H, 2H-C(1')); 5.51 (br. (40), 149 (7), 146 (20), 145 (20), 144 (loo), 131 (X), 120 ( 2 9 , 107 (7), 106 (20), 105 (17), 104 (IS), 79 (S), 78 (5), 77 (35), 51 (7), 39 (3). (3).…”

N,N′,N′′,N′′′-Tetrakis(2,6-dimethylphenyl)hexane-2,3,4,5-tetraimine

“…The addition of organolithium compounds to isonitriles is subject to various side reactions, notably -deprotonation (Walborsky et al, 1970(Walborsky et al, , 1971Niznik et al, 1974;Hirowatari & Walborsky, 1974;Niznik & Walborsky, 1974;Periasamy & Walborsky, 1974). In the absence of -H atoms, however, isonitriles show carbene-like reactivity, giving lithioimines; subsequent reaction with electrophiles gives imine derivatives, which may be desired in their own right (Walborsky & Roman, 1978; Barluenga et al, 1988;Ito et al, 1984).…”