Novel asymmetric phenylselenium-induced lactamizations of olefinic amides: stereoselective routes to α- and β-amino acids

Se-Phenyl 3-(1H-indol-3-yl)selenoacrylate

“…A scan of the Cambridge Structural Database (CSD, Version 5.25, updated July 2004;Allen, 2002) for organic molecules containing a CÐSeÐPh fragment (329 hits) gives a single occurrence with such disorder (Zeng et al, 2002), where an Se atom is disordered over two positions with occupation factors 0.90 and 0.10, respectively. In two cases, an approximate 1:1 disorder for an Se site was reported, but this induced two sets of positions for the phenyl group attached to the heavy atom (Chung et al, 1998;Kocienski et al, 2000). In spite of the disorder observed in (I), the geometry around the Se atom is unexceptional when compared to that found in numerous Secontaining compounds (Table 1).…”

Synthesis of 2,3,4,5-tetrahydro-1H-pyrrolo[1,2-a][1,4]diazepines and 11-methyl-2,3,4,5-tetrahydro-1H-[1,4]diazepino[1,2-a]indoles

“…12e, 14−15 We now report a direct and convenient approach for the synthesis of 2-(1H-1,2,3- (8) by the condensation of 3-(pyrrol-1-yl)-1-propylamine (1) and 3-(3-methyl-indol-1-yl)-propylamine (7) respectively with (1-hydroxymethyl)benzotriazole, followed by the substitution of the benzotriazole residue by a variety of nucleophiles.…”

“…2 They act as antitumor antibiotics with sequence selective DNA binding ability, 3 and antagonists of arginine vasopressin. 4 Syntheses of 1,4-diazepines fused with five and six membered heterocyclic rings, [5][6][7] and octahydropyrrolopyrazines [8][9] are well explored. Two reports address the synthesis of tetrahydropyrrolodiazepines (Scheme 1): (i) Okawara et al 10 synthesized 2-substituted-1-carboxy-2,3,4,5-tetrahydro-1H-pyrrolo[1,2-a] [1,4]diazepines by the reaction of 3-(pyrrol-1-yl)-1-propylamine with the glyoxalic acid hydrate in ethanol; (ii) bromopyrrolodiazepines (isolated from marine sponges) were synthesized by Marchais et al 11 via regioselective intramolecular cyclization of 2-substituted pyrroles.…”

Carboxybenzyl Group as an O-Nucleophile in the C–H Allylic Oxidation: Total Synthesis of (−)-Castanospermine

“…Standard procedures with tin and silicon hydrides ( n -Bu 3 SnH, Ph 3 SnH, (TMS) 3 SiH in toluene, 80–110 °C) under free radical conditions (AIBN as initiator) suffered from very low conversions. Only a rarely used methodology, involving in situ produced nickel boride, furnished the desired alcohol 7 (Scheme ).…”