G Model
CCLET-3250; No. of Pages 5
Chinese Chemical Letters
Original article
Propylphosphonic anhydride (T3P1) catalyzed one-pot synthesis of
-aminonitriles
a
Sirigireddy Sudharsan Reddy, Bhoomireddy Rajendra Prasad Reddy,
*
Peddiahgari Vasu Govardhana Reddy
Department of Chemistry, Yogi Vemana University, Kadapa 516003, Andhra Pradesh, India
A R T I C L E I N F O
A B S T R A C T
Article history:
The Strecker reaction was performed via a one-pot three component condensation of hetero aromatic/
Received 30 November 2014
Received in revised form 22 January 2015
Accepted 5 February 2015
Available online xxx
aromatic aldehydes, secondary amines and trimetylsilyl cyanide in the presence of propylphosphonic
anhydride (T3P1) to accomplish the corresponding
a
-aminonitriles. The main advantages of this
method are very short reaction time and excellent yields.
ß 2015 Peddiahgari Vasu Govardhana Reddy. Published by Elsevier B.V. on behalf of Chinese Chemical
Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. All rights reserved.
Keywords:
Strecker reaction
a-Aminonitriles
Propylphosphonic anhydride
5-Fluoro-3-methyl-2-carbaldehyde
1. Introduction
handle, highly soluble in organic solvents, and more effective as a
cyanide anion source for the nucleophilic addition of imines under
The Strecker reaction [1] provides one of the most efficient
methods for the synthesis of -aminonitriles, which are useful
mild conditions compared to other cyanating reagents [23]. Other
modifications to the Strecker reaction use catalysts, such as InCl3
[24], BiCl3 [25], montmorillonite KSF clay [26], silica bonded
scandium (III) [27], SO4/ZrO2 [28], ferric perchlorate [29],
Fe(Cp)2PF6 [30], InI3 [31], I2 [32], K5CoW12O40ꢀ3H2O [33], vanadyl
triflate [34], Fe3O4 [35], guanidine hydrochloride [36], xanthan
sulfuric acid [37], [bmim]BF4 [38], silica sulfuric acid [39],
hydrophobic sulfonic acid based nanoreactors [40] and silica-
bonded S-sulfonic acid [41] under various conditions. However,
many of these protocols suffer from disadvantages such as strongly
acidic conditions, unsatisfactory yields, and longer reaction times
in addition to tedious aqueous workups leading to the generation
of a large amount of toxic waste and use of stoichiometric or
relatively expensive reagents. Therefore, there is motivation to
explore a milder, safer, and more efficient catalyst for the synthesis
a
intermediates in the preparation of many amino acids and various
nitrogen containing heterocycles such as imidazoles, thiadiazoles,
etc. [2] and other biologically useful molecules such as saframycin-
A, a natural product with antitumor activity, or phthalascidin, a
synthetic analog, which exhibits even greater potency [3]. They are
usually prepared by the nucleophilic addition of a cyanide anion to
imine intermediates. Numerous methods have been reported
describing the preparation of a-aminonitriles [4–15]. The classical
Strecker reaction is generally carried out with hydrogen cyanide or
alkaline cyanides in aqueous solution. To overcome these
limitations, several modifications of the Strecker reaction have
been reported [16]. These modifications use alternative cyanating
sources, such as hydrogen cyanide (HCN) [17], potassium cyanide
(KCN) [18], sodium cyanide (NaCN), trimethylsilyl cyanide
(TMSCN) [19], diethylphosphorocyanidate ((OEt)2P(O)CN) [20],
bis(dialkyl amino cyano)borans, diethyl aluminum cyanide
(Et2AlCN) [21] and tributyltin cyanide (Bu3SnCN), etc. [22] under
various reaction conditions. Among these cyanide agents,
trimethylsilyl cyanide, has proven to be relatively safe, easy to
of
a
-aminonitriles within short reaction times. T3P1 is a well
known green coupling reagent and a powerful water scavenger
with several advantages, including low toxicity, low allergic
potential, broad functional group tolerance, generation of products
in excellent yield, purity, and easy workup procedures due to the
formation of water soluble byproducts [42–44]. Furthermore T3P1
has been investigated extensively in the preparation of various
heterocyclic compounds.
Though several works focused on the synthesis of
a-aminoni-
*
Corresponding author.
triles have been reported, the preparation of -aminonitriles from
a
1001-8417/ß 2015 Peddiahgari Vasu Govardhana Reddy. Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy
of Medical Sciences. All rights reserved.
Please cite this article in press as: S.S. Reddy, et al., Propylphosphonic anhydride (T3P1) catalyzed one-pot synthesis of
a-aminonitriles,