- Synthetic approaches to N- and 4-substituted 1,4-dihydro-3(2H)-isoquinolinone derivatives
-
Reaction of methyl-2-(2-formylphenyl)acetate with primary amines in a reductive amination/cyclisation process resulted in N-substituted 1,4-dihydro-3(2H)-isoquinolinones. With H2NCH2R sodium borohyride is a suitable reductant (11 examples), but H2NCHR1R2 required a transfer hydrogenation using ammonium formate catalysed by palladium on carbon (9 examples). 4-Substituted-1,4-dihydro-3(2H)-isoquinolinones were synthesised by deprotonation (n-butyllithium) and addition of R3CH2Br (12 examples with R3 = alkyl, Ar, CH[dbnd]CH2, C[tbnd]CH). Modest diastereoselectivity was achieved with 1,4-dihydro-3(2H)-isoquinolinones derived from H2NCHMeR2 [R2 = (η5-C5H4)Co(η4-C4Ph4) - max. dr = 1.9 : 1], but use of H2NCHMeFc (Fc = ferrocenyl) provided a new method of 1,4-dihydro-3(2H)-isoquinolinone N-deprotection with formic acid.
- O’ Sullivan, Michael J.,Hatley, Richard J.D.,Wellaway, Christopher R.,Bew, Sean P.,Richards, Christopher J.
-
-
- Iridium-Catalyzed Single-Step N-Substituted Lactam Synthesis from Lactones and Amines
-
Catalytic lactam synthesis was achieved directly from lactones and amines using an Ir catalyst. Three sequential transformations - aminolysis of lactone, N-alkylation of amine with hydroxyamide, and intramolecular transamidation of aminoamide - afforded the corresponding N-substituted lactams. (Figure Presented).
- Kim, Kicheol,Hong, Soon Hyeok
-
p. 4152 - 4156
(2015/05/04)
-
- Access to β-lactams by enantioselective palladium(0)-catalyzed C(sp3)-H alkylation
-
β-Lactams are very important structural motifs because of their broad biological activities as well as their propensity to engage in ring-opening reactions. Transition-metal-catalyzed C-H functionalizations have emerged as strategy enabling yet uncommon h
- Pedroni, Julia,Boghi, Michele,Saget, Tanguy,Cramer, Nicolai
-
p. 9064 - 9067
(2014/09/17)
-
- Aminocarbene Complexes of Chromium. 8. Access to the Pyrroloindole and Pyrrolochinoline Frameworks and Synthesis of Substituted Lycoranes
-
The use of alkynylaminocarbene complexes of chromium as starting material for the synthesis of pyrroloindole, pyrrolochinoline, and azaacenaphtylenone skeletons via cascade insertions of alkynes and CO followed by the rearrangement of zwitterionic intermediates was examined. Both the precursor complexes, synthesized from the appropriate functionalized lactams, as well as their thermolysis products were obtained in satisfactory yields and could be fully characterized. This reaction was finally applied to the synthesis of substituted lycoranes, a result which confirmed its general scope.
- Bouaucheau, Cecile,Parlier, Andree,Rudler, Henri
-
p. 7247 - 7259
(2007/10/03)
-
- Synthetic approaches to 2-substituted 1-oxo- and 3-oxotetrahydroisoquinolines
-
2-Substituted homophthalimides 2a-c were reduced regioselectively with sodium borohydride to carbinol-lactam intermediates 3a-c, which were dehydrated, followed by hydrogenation, to give 1-oxotetrahydroisoquinolines or 3,4-dihydroisoquinolin-1(2H)ones 5a-c. The isomeric 3-oxo-tetrahydroisoquinolines or 1,4-dihydroisoquinolin-3(2H)-ones 8a-i were obtained in satisfactory yields via heating 3-isochromanone (6) with the corresponding amines 7a-i in the presence of aluminum chloride.
- Cheng,Tsai,Lin
-
-