Use of Silver Carbonate in the Wittig Reaction

The Wittig Reaction

The Wittig Reaction

This so-called Wittig reaction has a number of advantages over other olefination methods; in particular, it occurs with total positional selectivity (that is, an alkene always directly replaces a carbonyl group). By comparison, a number of other carbonyl olefination reactions often occur with double-bond rearrangement. In addition, the factors that influence Eand Z-stereoselectivity are well un...

learners’ attitudes toward the effectiveness of mobile-assisted language learning (mall) in vocabulary acquisition in the iranian efl context: the case of word lists, audiobooks and dictionary use

رشد انفجاری تکنولوژی فرصت های آموزشی مهیج و جدیدی را پیش روی فراگیران و آموزش دهندگان گذاشته است. امروزه معلمان برای اینکه در امر آموزش زبان بروز باشند باید روش هایی را اتخاذ نمایند که درآن ها از تکنولوژی جهت کمک در یادگیری زبان دوم و چندم استفاده شده باشد. با در نظر گرفتن تحولاتی که رشته ی آموزش زبان در حال رخ دادن است هم اکنون زمان مناسبی برای ارزشیابی نگرش های موجود نسبت به تکنولوژی های جدید...

Mechanism of the Phospha-Wittig–Horner Reaction**

General. All reactions were performed under argon using Schlenk techniques. Diethyl ether and THF were freshly distilled from sodium/benzophenone prior to use. 1 H, 13 C and 31 P spectra were recorded on a 400 MHz and 300 MHz spectrometers. Chemical shifts (ppm) were reported and referenced to the internal signal of residual protic solvent. High resolution mass spectral analyses (HRMS) were per...

comparative analysis of the use of hedges & emphatics in english and persian academic research articles of sociology & psychology

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