[Bis(2-methoxyethyl)amino]sulfur Trifluoride, the Deoxo-Fluor Reagent: Application toward One-Flask Transformations of Carboxylic Acids to Amides
摘要:
The use of the Deoxo-Fluor reagent is a versatile method for acyl fluoride generation and subsequent one-flask amide coupling. It provides mild conditions and facile purification of the desired products in good to excellent yields. We have explored the utility of this reagent for the one-flask conversion of acids to amides and Weinreb amides and as a peptide-coupling reagent.
Raman and infrared spectra, conformational stability, vibrational assignment and ab initio calculations of but-2-enoyl fluoride
作者:James R. Durig、Gamil A. Guirgis、Yanping Jin
DOI:10.1016/0022-2860(95)09149-1
日期:1996.6
Abstract The Raman (3500-10 cm −1 ) and infrared (3200-50 cm −1 spectra have been recorded of the fluid and solid phases of but-2-enoyl fluoride (crotonyl fluoride) trans -CH 3 CHCHCFO, where the methyl group is trans to the CFO group. From the variable temperature studies of the infrared spectrum of the sample dissolved in liquified Xe, the conformer pair at 836 827 cm −1 has been used to determine
似乎对反式构象异构体略有偏爱。s-trans 构象异构体的不对称扭转基波在 104.3 cm -1 处观察到两个热带,而 s-cis 旋转异构体在 97.0 cm -1 处观察到一个热带。根据这些数据,确定了构象交换的势函数,势系数为:V 1 = -122 ± 1,V 2 = 1993 ± 27,V 3 = 21 ± 1 和 V 4 = -88 ± 8 cm - 1 . s-trans 到 s-cis 和 s-cis 到 s-trans 势垒分别测定为 2044 和 1942 cm -1 ,构象异构体之间的焓差为 102 ± 29 cm -1 (292 ± 83 cal mol -1 )。控制 s-trans 和 s-cis 构象异构体的 CH 3 基团内部旋转的势垒计算为 1060 ± 17 cm -1 (3.03 ± 0.05 kcal mol -1 ) 和 1042 ± 23 cm -1
Acyl tetramic acids. 6. Synthesis of 3-dienoyl tetramic acids related to streptolydigin and tirandamycin
作者:Ving J. Lee、Alan R. Branfman、Thomas R. Herrin、Kenneth L. Rinehart
DOI:10.1021/ja00481a036
日期:1978.6
Dicobalt hexacarbonyl complexes of conjugated enynes as equivalents of tetradentate synthons for the preparation of bicyclo [3.3.0] octanes
作者:A. S. Gybin、V. A. Smit、A. L. Veretenov、S. O. Simonyan、A. S. Shashkov、Yu. T. Struchkov、L. G. Kuz'mina、R. Caple
DOI:10.1007/bf00962438
日期:1989.12
Gybing; Smit; Caple, Journal of the American Chemical Society, 1992, vol. 114, # 14, p. 5555 - 5566