109902-33-2Relevant articles and documents
3H-1,3-Azaphospholo[4,5-b]pyridines-novel heterocyclic P,N-bridging or hybrid ligands: Synthesis and first d8-transition metal complexes
Adam, Mohamed Shaker S.,Kindermann, Markus K.,Jones, Peter G.,Heinicke, Joachim W.
, p. 2261 - 2272 (2016)
The first 3H-1,3-azaphospholo-pyridines 2a-c were synthesized as racemic mixtures in modest to medium yield by the reaction of N-(2-chloropyrid-3-yl)-trimethylacetimidoyl chloride 1 with RPLi2 (R = Ph, n-Bu, i-Bu), generated from RPH2/sub
Synthesis of 3-aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP)
Niu, Chuansheng,Li, Jun,Doyle, Terrence W.,Chen, Shu-Hui
, p. 6311 - 6318 (2007/10/03)
Palladium-catalyzed cross-coupling of methylboronic acid with 2-chloro- 3-nitropyridine produced 2-methyl-3-nitropyridine 4 in one step in high yield. Oxidation of 4 with selenium dioxide gave aldehyde 5. Alternatively, condensation of 4 with DMFDMA followed by oxidation gave 5 in a two step higher yielding conversion. Subsequent direct coupling of 5 with thiosemicarbazide followed by reduction of the nitro group using stannous chloride or sodium sulfide provided 3-AP (3). Reduction with sodium hydrosulfite gave 3-HAP (8). Finally a route which avoids the reduction of a nitro function was devised. Thus direct coupling of styrene with 2-chloro-3- aminopyridine 9 under Heck reaction conditions gave 16 which was converted to 17, oxidized to the aldehyde 18 and converted to 3-AP (3) with in situ deblocking of the t-Boc functionality.