1 - benzyl - 5 - formyl - 2 - methyl

Methan (Benzyl-ethyl-amino)-(formyl-methyl-amino)- E14a/3, 563 (CH20 + HjC-NH-CHO/SOCl2 R2NH) 1,2,5-Oxadiazin 5-Phenyl-2-propyl-tetrahydro- E16a, 312 (aus Imidazolidin)... 

Benzol 3-Acetamino-2-(formyl-methyl)-l -(2-methoxy-2-hydro-peroxy-ethyl)- IV/la, 31 Bernsteinsaure 2-(N-Benzyl-... 

I, 4- and 3,4-Dihydroquinazolines are tautomeric but any attempts to prepare the former w ithout a 1-substituent have led to the latter. The greater stability to proto tropic change of 1,2-dihydronaphthalene over 1,4-dihydronaphthalene is also found in 3,4-dihydroquinazoline. Earlier claims to the preparation of l,4-dihydroquinazolines ° were erroneous and based on incomplete experimental data. The first 1,4-dihydroquinazoline was prepared as recently as 1961. 1-Methyl and l-benzyl-l,4-dihydroquinazolines were obtained from o-methylamino-and o-benzylamino-benzylamines (42) by formylation and ring closure. Attempts to remove the benzyl group gave 3,4-dihydroquinazoline. These 1,4-dihydro compounds are susceptible to oxidation, and attempts made to prepare 1,2-dimethyl-1,4-dihydroquinazoline from o-... 

Dimethylamino-methyl)-2-hydroxymethyl-aus 2 -Carboxy-2-(dimethylaminocarbonyl)-biphenyl und Lithiumalanat 165 2,2 -Dinitro- 474, 476, 695 6,6 -Dinitro-2,2 -bis-[chlorcarbonyl]- 188 2,2 -Dinitro-4,4 -bis-[diathylamino]- 695 4,4 -Dinitro-2,2 -bis-rhydroxymethyl]- 213 6,6 -Dinitro-2,2 -bis-[hydroxymethyl]- 188 2,2 -Dinitro-4,4 -diamino- 695 6,6 -Dinitro-2,2 -diformyl- 694 4,4 -Dinitro-2,2 -dimethoxycarbonyl- 213 2,2 -Dinitro-4,4 -dimethyl- 695 6,6 -Dinitro-2 -formyl-2-carboxy- 694 2,2 -Dinitroso- 476 -4-hydroxamsaure-chlorid 537 4-(a-Hydroxy-benzyl)- 542 Methoxy- 678 2-Methyl- 556 Nitro- 672, 678 4-Nitro- 687... 

Reduction of 3-benzyl-8-chloro-4-oxo-4//-pyrido[l,2- ]pyrimidine-2-carboxylate <2004W004/064741> and 2-methyl-4-oxo-4//-pyrido[l,2-tf]pyrimidine-3-carboxylate <2003T4123> with DIBAL-H afforded 2- and 3-formyl derivatives, respectively. Reduction of /V-(4-fluorobenzyl)-3-hydroxy-8-[methoxy(methyl)amino]-4-oxo-6,7,8,9-tetra-hydro-4//-pyrido[l,2- ]pyrimidine-2-carboxamide with Zn-dust in aqueous AcOH afforded the 8-methylamino derivative, which was acylated with AcOH in the presence of Hiinig s base, HOBt, and l-(3-dimethylaminopro-pyl)-3-ethylcarbodiimide-HCl <2004W004/058756>. 3-(Perhydropyrido[l,2- ]pyrimidin-2-yl)propylamine was obtained by catalytic hydrogenation of 2-(perhydropyrido[l,2- ]pyrimidin-2-yl)propionitrile over a Pt02 catalyst <2003FRP1275647>. 

Dihydro-2(l,3-dimethyluracil-5-yl)-l,3,4-oxadiazole was obtained in 53% yield by the [3+2] cycloaddition of diazomethane to the formyl group of l,3-dimethyl-5-formyluracil <1997T7045>. The reaction of l-acetyl-2-benzyl-hydrazine with methyl glyoxalate in toluene afforded an oxadiazolidine derivative <1996TL4323>. 

Dimethylcyclohexanone and 2-benzyl-2-methylcyclohex-anone have been prepared similarly in yields of 60% and 55%, respectively.2 The procedure has been extended to the synthesis of 9-methyl-, 9-w-butyl-, and 9-benzyl-l-decalone from the dianion of 2-formyl-l-decalone in yields of 55%, 48%, and 58%, respectively.2... 

Brom-5-formyl-l-( 4-methoxy-henzyl)-imidazol l-Benzyl-4-brom-5-carboxy-...946 /-Benzyl-4-brom-5-mercapto-...946 4-Brom-5-methoxycarbonyl-]-methyl-...1047 1033 50% 67% 68% 50% ... 

A novel method of opening of oxiranes involves the use of (chlo-romethylene)dimethyliminium chloride (39) [see Section II,2c p. 250], monochlorodeoxy or dichlorodideoxy derivatives are obtained, depending upon the reaction conditions employed.83 Thus, methyl 2,3-anhydro-4,6-0-benzylidene-a-D-allopyranoside (110) reacts with 39 in 1,1,2,2-tetrachloroethane at room temperature to give, upon hydrolysis of the primary adduct 111 with an aqueous solution of sodium hydrogen carbonate, methyl 4,6-0-benzylidene-2-chloro-2-deoxy-3-0-formyl-a-D-altropyranoside (112). If a solution of 39 and 110 in 1,1,2,2-tetrachloroethane is heated at reflux temperature, methyl 3,4-0-benzylidene-2,6-dichloro-2,6-dideoxy-o -D-altropyrano-side (113) is obtained in high yield the n.m.r. spectrum of 113, like that of 47 (see Section II, 2c p. 250), showed the presence of two diastereoisomers which differed in the configuration of the benzyl-idene-acetal carbon atom. 

---