Selective reduction of aliphatic ketones and aldehydes to hydrocarbons with sodium cyanoborohydride and p-toluenesulfonyl hydrazide in dimethylformamide-sulfolane

Total synthesis of (+-)-4-deoxydamsin. Structure correlation of pseudoguaianolide sesquiterpenes

“…Addition of thiophenol12 afforded the adduct 15, which was condensed with p-toluenesulfonylhydrazine and then reduced with sodium cyanoborohydride to give the deoxy derivative 16. 13 Chart IIa a a, PhSH; b, TsNHNH2; c, NaBHgCN; d, m-ClC6H4C03H; e, heat, CHgPh.…”

Sulfonic acid anchored on silica, SiO2@SO3H: A superior solid acid catalyst for quick and solvent‐free reductive‐deoxygenation of ketones with NaBH3CN

“…In this context, considerable attention has been paid to modified hydroborate agents for reduction of organic compounds . NaBH 3 CN with an electron withdrawing cyano group is a remarkable stable and selective reducing agent and has been found many applications in organic synthesis . In addition, it is well known that the reducing capability of NaBH 3 CN for reduction of functional groups is greatly modified with pH variations.…”

“…[1][2][3][4] NaBH 3 CN with an electron withdrawing cyano group is a remarkable stable and selective reducing agent and has been found many applications in organic synthesis. [5][6][7][8][9][10][11][12][13][14][15][16] In addition, it is well known that the reducing capability of NaBH 3 CN for reduction of functional groups is greatly modified with pH variations. Thus in basic or neutral media, functional groups such as the carbonyl moiety are practically inert toward NaBH 3 CN, and the adequate reduction rate is obtained when the reaction medium gets acidic conditions (pH~3-4).…”

Total Syntheses of (−)‐Conidiogenone B, (−)‐Conidiogenone, and (−)‐Conidiogenol

“…Wolff-Kishner-Huang-Minlon reduction [18] of ketone 25 was problematic since the desired full reduction product 14 was obtained in only 37 % yield. Modified Wolff-Kishner reduction of tosylhydrazone 30 also proved to be ineffective with a variety of different reducing agents such as NaBH 3 CN, catecholborane, LiAlH 4 , or Dibal-H. [19] Nevertheless, a threestep Barton-McCombie deoxygenation approach successfully afforded tetracycle 14 in 51 % overall yield. [20] With the requisite angular triquinane framework in hand, we began to investigate the ring-enlargement process.…”