The role of an aromatic group in remote chiral induction during conjugate addition of α-sulfonylallylic carbanions to ethyl crotonate

• Shlomo Levinger,
• Ranjeet Nair and
• Alfred Hassner

Beilstein J. Org. Chem. 2008, 4, No. 32, doi:10.3762/bjoc.4.32

• cyanoborohydride in an acidic medium. Phenyl-, (4-nitrophenyl)- and (1-naphthyl)ethylamines 6a, c, e are commercial. Interestingly, the 9-anthryl nucleus in both primary amine 6h and its allyl sulfone congener 1h shows a peculiar 1H NMR spectrum: a broad signal representing both protons 1 and 8 in the first

Perhalogenated pyrimidine scaffolds. Reactions of 5-chloro- 2,4,6-trifluoropyrimidine with nitrogen centred nucleophiles

• Emma L. Parks,
• Graham Sandford,
• John A. Christopher and
• David D. Miller

Beilstein J. Org. Chem. 2008, 4, No. 22, doi:10.3762/bjoc.4.22

• 2,4,6-trifluoropyrimidine with ammonia is reported [20] to give two products in a 4 : 1 ratio and a primary amine, ethanolamine, gave a 2 : 1 ratio of products. Therefore, reactions of 1 with nitrogen centred nucleophiles are more selective than 2,4,6-trifluoropyrimidine despite the increased steric

New acylides: synthesis of 3-O-[γ-(4-oxo-2-aryl- thiazolidin- 3-yl)butyryl]erythromycin A derivatives

• Deepa Pandey,
• Wahajul Haq and
• Seturam B. Katti

Beilstein J. Org. Chem. 2008, 4, No. 14, doi:10.3762/bjoc.4.14

• -thiazolidin-3-yl)butyryl]erythromycin A derivatives have been synthesized. The 3-hydroxy group was derivatised to a primary amine and subsequently the thiazolidinone nucleus was generated at the amino functionality through DCC mediated one-pot three-component reaction in good yields. Background Second

Analogues of amphibian alkaloids: total synthesis of (5R,8S,8aS)-(−)-8-methyl- 5-pentyloctahydroindolizine (8-epi-indolizidine 209B) and [(1S,4R,9aS)-(−)-4-pentyloctahydro- 2H-quinolizin- 1-yl]methanol

• Joseph P. Michael,
• Claudia Accone,
• Charles B. de Koning and
• Christiaan W. van der Westhuyzen

Beilstein J. Org. Chem. 2008, 4, No. 5, doi:10.1186/1860-5397-4-5

• -benzyl-1-phenylethylamine, was converted into the primary amine (−)-15 and thence in several steps into the thiolactam (+)-16. Eschenmoser sulfide contraction [22][23] with ethyl bromoacetate yielded the key enaminone intermediate (+)-17, chemoselective reduction of the saturated ester of which produced

Variations in product in reactions of naphthoquinone with primary amines

• Marjit W. Singh,
• Anirban Karmakar,
• Nilotpal Barooah and
• Jubaraj B. Baruah

Beilstein J. Org. Chem. 2007, 3, No. 10, doi:10.1186/1860-5397-3-10

• the literature that the reaction of N-phenyliminophosphorane with 1,2-naphthoquinone results in the formation of 2-anilino-naphthoquinone-1,4-anil [14] and in our present investigation we have observed that such products can be prepared just by reaction of 1,2-naphthoquinone with a primary amine

• rings are perpendicular to each other. The C-S bond formation reaction can be extended to other thiols such as thiophenol and 4-methoxythiophenol, 4-bromothiophenol etc. with 1,4-naphthoquinone as well as 1,4-benzoquinone. The difference in the case of reaction of 1,4-benzoquinone with primary amine

Synthesis of coumarin or ferrocene labeled nucleosides via Staudinger ligation

• Ivana Kosiova,
• Andrea Janicova and
• Pavol Kois

Beilstein J. Org. Chem. 2006, 2, No. 23, doi:10.1186/1860-5397-2-23

• primary amine and triarylphosphine oxide. This Staudinger reduction is a frequently used method for the smooth reduction of azides to amines. Iminophosphoranes can react with almost any kind of electrophilic reagent, [15][16] e.g. aldehydes or ketones to form imines. Also less reactive carbonyl

Synthesis and glycosidase inhibitory activity of new hexa- substituted C8-glycomimetics

• Olivia Andriuzzi,
• Christine Gravier-Pelletier,
• Gildas Bertho,
• Thierry Prangé and
• Yves Le Merrer

Beilstein J. Org. Chem. 2005, 1, No. 12, doi:10.1186/1860-5397-1-12

• aminocyclitols it could be an epoxidation followed by the nucleophilic opening of the epoxide moiety by a primary amine or another nitrogen nucleophile. Accordingly (Scheme 1), treatment of the fully O-protected L-ido-cyclooctene 1 with a 5 mol% aqueous solution of osmium(IV) tetroxide [34] in acetone in the

• , which crystallizes as a dimer, constituted by a tricyclic system [5-8-5] adopts a more flexible boat-chair conformation, thus allowing its opening by a linear nucleophile (azide anion), but not by a more hindered nucleophile (primary amine). With the key enantiomerically pure azido-alcohol 11 and 12 in