Reference

Geminal alkylation in carbohydrate chemistry

Geminal alkylation in carbohydrate chemistry. Conversion of L-glutamic acid into gem-di-C-methyl carbohydrate derivatives, and synthesis of 6-chloro-9-(5,5-dimethylfuran-2-yl)purine. Szarek, Walter A.; Yvas, Dolatrai M.; Chen, Lu-Yu (Dep. Chem., Queen's Univ.Some commonly used reagents like 56-86-0 and 32780-06-6 are used in this experiment., Kingston, Ont., Can.). Carbohydr. Res., 53(1), C1-C4 (English) 1977. CODEN: CRBRAT. DOCUMENT TYPE: Journal CA Section: 33 (Carbohydrates) Section cross-reference(s): 34, 27, 28 Deamination-esterification of L-glutamic acid followed by redn., benzylation, treatment with MeMgI, and hydrogenolysis over Pd/C gave the key intermediate I. Oxidn. of I with NaIO4 gave the gem-di-C-methyl II. Reaction of II with 6-chloropurine, (EtO2CN:)2, and Ph2PMe in THF at room temp. gave the nucleoside analog III. .

Dimethyl 2-oxo-5S-hydroxydeca-6E,8E-dienylphosphonate

Dimethyl 2-oxo-5S-hydroxydeca-6E,8E-dienylphosphonate. (Suntry Ltd., Japan). Jpn. Kokai Tokkyo Koho JP 58188890 A2 4 Nov 1983 Showa, 4 pp. (Japanese). (Japan). CODEN: JKXXAF. CLASS: IC: C07F009-40. APPLICATION: JP 82-70832 26 Apr 1982. DOCUMENT TYPE: Patent CA Section: 29 (Organometallic and Organometalloidal Compounds) Title compd. (5S)-MeCH:CHCH:CHCH(OH)CH2CH2COCH2P(O)(OMe)2 (I) was prepd. starting with II and PhCH2OCH2Cl (III). Thus, addn. of 2.86 g III to a mixt. of 1.41 g II and 4.7 g (Me2CH)2NEt in CH2Cl2 at 0° and stirring 5 h at room temp. gave 54% IV, which (1.904 g) was treated with 0.25 mL 0.16 M LiOMe/MeOH, 1.Several reagents with their cas registry numbers 88711-46-0 and 32780-06-6 are used here.38 g imidazole and 1.22 g Me3CSiMe2Cl in DMF at room temp. to give 51% (4S)-PhCH2OCH2OCH2CH(OSiMe2CMe3)CH2CH2CO2Me (V). Hydrogenation of 1.56 g V in EtOH contg. 220 mg Pd black under 1 atm H at room temp. gave 98% (4S)-HOCH2CH(OSiMe2CMe3)CH2CH2CO2Me, which (3.52 g) was treated with a mixt. of 12.75 g pyridine and 8.06 g CrO3 in CH2Cl2 at room temp. to give 79% (4S)-OHCCH(OSiMe2CMe3)CH2CH2CO2Me (VI). Addn. of 2.73 g VI in THF to a mixt. of 2.264 g trans-MeCH:CHSOPh and 1.5 M LiBu/hexane in THF at -78°, treatment with 2.18 mL Ac2O at room temp., extn. with Et2O, addn. of 42 g 3% Na-Hg to the concd. ext. in AcOEt-MeOH at -30°, and stirring at -24° gave 75% (4S)-MeCH:CHCH:CHCH(OSiMe2CMe3)CH2CH2CO2Me (VII). Addn. of 2.307 g VII in THF to a mixt. of 2.207 g di-Me methylphosphonate and 1.187 mL 1.5 M BuLi/hexane in THF at -78° and stirring the whole 30 min at room temp. gave 85% I. .